This preliminary prospectus supplement relates to an effective registration statement under the Securities Act of 1933, but the information in this preliminary prospectus supplement is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell and are not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

CubeSmart is offering 17,000,000 of its common shares of beneficial interest, par value $0.01 per share, or common shares.

Our common shares are traded on the New York Stock Exchange, or NYSE, under the symbol "CUBE." The last reported sale price of our common shares on the NYSE on October 21, 2011 was $9.58 per share.

We are organized and conduct our operations to qualify as a real estate investment trust, or REIT, for federal income tax purposes. To assist us in qualifying as a REIT, among other reasons, ownership of our outstanding common shares by any person is limited to 5.0% (in value or number of shares, whichever is more restrictive), subject to certain exceptions. In addition, our declaration of trust contains various other restrictions on the ownership and transfer of our common shares. See "Description of CubeSmart's Capital Shares — Restrictions on Ownership and Transfer" in the accompanying prospectus.

Investing in our common shares involves a high degree of risk. Before buying any common shares, you should carefully read the discussion of material risks of investing in our common shares under the heading "Risk Factors" beginning on page S-7 of this prospectus supplement and beginning on page 10 of our Annual Report on Form 10-K for the year ended December 31, 2010 for a discussion of certain risks that you should consider in connection with an investment in our common shares.

We have granted the underwriters a 30-day option to purchase up to an additional 2,550,000 common shares from us at the initial public offering price, less the underwriting discount, if the underwriters sell more than 17,000,000 common shares in this offering.

Neither the Securities and Exchange Commission, nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement and the accompanying prospectus are truthful or complete. Any representation to the contrary is a criminal offense.

You should rely only on the information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus or any applicable free writing prospectus filed with the Securities and Exchange Commission, or SEC, in connection with this offering. We have not, and the underwriters have not, authorized anyone to provide you with additional or different information. If any person provides you with additional or different information, you should not rely on it. Neither we nor the underwriter is making an offer to sell common shares in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus supplement, the accompanying prospectus, any such free writing prospectus and the documents incorporated by reference herein and therein is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed since those dates.

This document is in two parts. The first part is this prospectus supplement, which describes certain matters relating to us and this offering. The second part, the accompanying prospectus dated September 16, 2011, gives more general information about our common shares and other securities we may offer from time to time, some of which may not apply to this offering.

You should carefully read this prospectus supplement, the accompanying prospectus and the additional information incorporated by reference herein before investing in our common shares. See "Incorporation of Certain Information By Reference" and "Where You Can Find More Information" in this prospectus supplement. These documents contain important information that you should consider before making your investment decision. This prospectus supplement and the accompanying prospectus contain the terms of this offering of common shares. This prospectus supplement may add, update or change information contained in or incorporated by reference in the accompanying prospectus. If the information in or incorporated by reference in this prospectus supplement is inconsistent with any information contained in or incorporated by reference in the accompanying prospectus, the information in or incorporated by reference in this prospectus supplement will apply and will supersede the inconsistent information contained in or incorporated by reference in the accompanying prospectus.

As used in this prospectus supplement, unless the context otherwise requires, references to "CubeSmart" refer to CubeSmart, a Maryland real estate investment trust, or "REIT"; references to the "Operating Partnership" refer to CubeSmart, L.P., a Delaware limited partnership; and references to "we," "us," "our" or similar expressions refer collectively to CubeSmart and its consolidated subsidiaries (including the Operating Partnership).

This prospectus supplement and the accompanying prospectus, together with other documents and information incorporated by reference into this prospectus, contain certain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, or Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended, or Exchange Act. Such statements are based on assumptions and expectations that may not be realized and are inherently subject to risks, uncertainties and other factors, many of which cannot be predicted with accuracy and some of which might not even be anticipated. Although we believe the expectations reflected in these forward-looking statements are based on reasonable assumptions, future events and actual results, performance, transactions or achievements, financial and otherwise, may differ materially from the results, performance, transactions or achievements expressed or implied by the forward-looking statements contained in or contemplated by this prospectus supplement or the accompanying prospectus. Any forward-looking statements should be considered in light of the risks and uncertainties referred to in this prospectus supplement, the accompanying prospectus, our Annual Report on Form 10-K for the year ended December 31, 2010 and subsequently filed quarterly reports on Form 10-Q. The most significant of these risks, uncertainties and other factors that might cause such differences include, but are not limited to:

In light of these uncertainties and risks, prospective investors are cautioned not to place undue reliance on these forward-looking statements. Except with respect to such material changes to our risk factors as may be reflected from time to time in our quarterly filings or as otherwise required by law, we are under no obligation to, and expressly disclaim any obligation to, update or revise any forward-looking statements included or incorporated by reference in this prospectus supplement or the accompanying prospectus, whether as a result of new information, future events or otherwise. Because of the factors referred to above, the future events discussed in or incorporated by reference in this prospectus supplement or the accompanying prospectus may not occur and actual results, performance or achievement could differ materially from that anticipated or implied in the forward-looking statements.

The information below is only a summary of more detailed information included elsewhere in or incorporated by reference in this prospectus supplement and the accompanying prospectus. This summary does not contain all the information that is important to you or that you should consider before buying common shares in this offering. The other information is important, so please read carefully this prospectus supplement and the accompanying prospectus, as well as the information incorporated by reference.

CubeSmart is a self-administered and self-managed REIT focused primarily on the ownership, operation, acquisition and development of self-storage facilities in the United States.

As of September 30, 2011, we owned 353 self-storage facilities located in 26 states and in the District of Columbia containing an aggregate of approximately 23.3 million rentable square feet. As of September 30, 2011, approximately 80.4% of the rentable square footage at our owned facilities was leased to approximately 205,000 tenants, and no single tenant represented a significant concentration of our revenues. In addition, as of September 30, 2011, we managed 103 properties for third parties, bringing the total number of properties we owned and/or managed at September 30, 2011 to 456.

Our self-storage facilities are designed to offer affordable and easily-accessible storage space for our residential and commercial customers. Our customers rent storage units for their exclusive use, typically on a month-to-month basis. Additionally, some of our facilities offer outside storage areas for vehicles and boats. Our facilities are designed to accommodate both residential and commercial customers, with features such as security systems and wide aisles and load-bearing capabilities for large truck access. All of our facilities have an on-site manager during business hours, and many have a manager who resides in an apartment at the facility. Our customers can access their storage units during business hours, and some of our facilities provide customers with 24-hour access through computer controlled access systems. Our goal is to provide customers with the highest standard of facilities and service in the industry. To that end, as of September 30, 2011, a majority of our facilities included climate controlled units.

We own and manage self-storage facilities are located in the following states: Alabama, Arkansas, Arizona, California, Colorado, Connecticut, District of Columbia, Florida, Georgia, Illinois, Indiana, Louisiana, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, Tennessee, Texas, Utah, Virginia and Wisconsin.

Our self-storage facilities are located in major metropolitan areas as well as rural areas and have numerous tenants per facility. No single tenant represented a significant concentration of our 2010 revenues. Our facilities in Florida, California, Texas and Illinois provided approximately 17%, 12%, 10% and 7%, respectively, of our total revenues for the six months ended June 30, 2011.

Although our organizational documents do not limit the amount of debt that we may incur, we maintain a capital structure that we believe is reasonable and prudent and that will enable us to have ample cash flow to cover debt service and make distributions to our shareholders. We expect to finance additional investments in self-storage facilities through the most attractive available sources of capital at the time of the transaction, in a manner consistent with maintaining a strong financial position and future financial flexibility. These capital sources may include borrowings under the revolving portion of our unsecured credit facility and through additional secured financings, sales of common or preferred shares in public offerings or private placements, issuances of common or preferred units in the Operating Partnership in exchange for contributed properties or cash and formations of joint ventures. We also may sell facilities that we no longer view as core assets and reallocate the sales proceeds to fund other growth.

New self-storage facility development has intensified the competition among self-storage operators in many market areas in which we operate. Self-storage facilities compete based on a number of factors, including location, rental rates, security, suitability of the facility's design to prospective customers' needs and the manner in which the facility is operated and marketed. In particular, the number of competing self-storage facilities in a particular market could have a material effect on our occupancy levels, rental rates and on the overall operating performance of our facilities. We believe that the primary competition for potential customers of any of our self-storage facilities comes from other self-storage facilities within a three-mile radius of that facility. We believe our facilities are well-positioned within their respective markets and we emphasize customer convenience, security and professionalism.

Our key competitors include local and regional operators as well as the other public self-storage REITS, including Public Storage, Sovran Self Storage and Extra Space Storage Inc. These companies, some of which operate significantly more facilities than we do and have greater resources than we have, and other entities may generally be able to accept more risk than we determine is prudent for us, including risks with respect to the geographic proximity of facility investments and the payment of higher facility acquisition prices. This competition may generally reduce the number of suitable acquisition opportunities available to us, increase the price required to consummate the acquisition of particular facilities and reduce the demand for self-storage space in areas where our facilities are located. Nevertheless, we believe that our experience in operating, acquiring, developing and obtaining financing for self-storage facilities should enable us to compete effectively.

We were formed in July 2004 as a Maryland REIT. Effective September 14, 2011 we changed our name from "U-Store-It Trust" to "CubeSmart." We own our assets and conduct our business through the Operating Partnership and its subsidiaries. We control the Operating Partnership as its sole general partner and, as of September 30, 2011, we owned an approximately 95.4% interest in the Operating Partnership. The Operating Partnership has been engaged in virtually all aspects of the self-storage business, including the development, acquisition, ownership and operation of self-storage facilities.

Our executive offices are located at 460 East Swedesford Road, Suite 3000, Wayne, PA 19087 and our telephone number is (610) 293-5700.

On October 24, 2011, the Operating Partnership entered into a purchase agreement to acquire a portfolio of 22 open and operating self-storage facilities from Storage Deluxe that contain an aggregate of approximately 1.6 million rentable square feet, including a recently opened 50,000 square foot property located in Bronx, NY. The properties are located in Brooklyn, NY, Woodhaven, NY, Jamaica, NY, Yorktown, NY, Tuckahoe, NY, New Rochelle, NY, Bronx, NY, Wilton, CT, Shelton, CT and Norristown, PA. We refer to this acquisition in this prospectus supplement as the "Storage Deluxe Acquisition."

We consider 13 of the 21 operating assets in this portfolio to be at stabilized physical occupancy. These stabilized properties were 87.1% occupied at June 30, 2011. This segment of the portfolio has a weighted average date opened of December 2003. The remaining eight operating assets considered to have lease-up opportunity were 78.3% occupied at June 30, 2011, with a weighted average date opened of August 2007. The portfolio, excluding a development asset in Bronx, NY that opened in September 2011, was 84.0% occupied as of June 30, 2011. The weighted average population within the three-mile trade ring of the assets is 828,000 and 68% of the households are renters as of April 14, 2011 based on data from STDB Online.

The aggregate purchase price for the properties is approximately $560 million, comprised of approximately $472 million payable in cash and the assumption of approximately $88 million of existing fixed-rate debt. In connection with the execution of the purchase agreement, we are depositing approximately $45 million in escrow as earnest money. In addition to the purchase price, we expect to incur approximately $4.6 million of acquisition costs in connection with the Storage Deluxe Acquisition.

We expect to consummate the acquisition in two tranches. We anticipate closing on the purchase of 16 unencumbered properties with a purchase price of approximately $357.3 million during the fourth quarter of 2011. We anticipate closing on the purchase of the remaining properties with a purchase price of approximately $202.7 million, including the assumption of $88 million of secured fixed-rate debt, immediately following completion of the loan assumption process which we expect to occur during the first quarter of 2012, except that closing under two of these remaining properties may be further extended in order to secure certain third party consents.

The consummation of the Storage Deluxe Acquisition is subject to satisfactory examination of the title to the properties, the ability to obtain title insurance, receipt of estoppels from ground lease lessors related to the leases to be assigned, execution of an additional lease at one facility with an affiliate of the seller, lender consents to the assumption of $88 million of secured fixed-rate debt and customary closing conditions, including the receipt of third party consents. We cannot assure you that we will be able to complete the acquisition of these properties as anticipated or at all.

We expect to finance a portion of the cash purchase price with the proceeds of this offering, as well as a combination of borrowings under the revolving portion of our unsecured credit facility, additional secured or unsecured financings, sales of preferred shares in public offerings or private placements or the bridge financing facilities described below. We are in the process of continuing to finalize these sources of financing and cannot assure you that any or all of these sources of financing will be available to us, on favorable terms or at all.

In order to ensure that financing will be available to consummate the Storage Deluxe Acquisition, we have received $300.0 million of combined bridge financing facilities from affiliates of Wells Fargo Securities, LLC, the underwriter for this offering. Under these facilities, an affiliate of Wells Fargo Securities, LLC has agreed to purchase, upon our request and subject to certain conditions, up to $200.0 million in aggregate liquidation preference of a new series of our cumulative redeemable preferred shares, which we refer to as our Preferred Equity Line. Another affiliate of Wells Fargo Securities, LLC has agreed to provide us with a $100.0 million new unsecured term loan facility, which will mature within six months with the ability to extend for an additional five years. We refer to this term loan facility as the Storage Deluxe Acquisition Bridge Facility.

Each of the Preferred Equity Line and Storage Deluxe Acquisition Bridge Facility are currently undrawn. The commitments under the Preferred Equity Line are available until March 31, 2012 and the commitments under the Storage Deluxe Acquisition Bridge Facility are available until April 30, 2012. The commitments under the Storage Deluxe Acquisition Bridge Facility are subject to certain conditions. We intend to use proceeds from the Preferred Equity Line or Storage Deluxe Acquisition Bridge Facility, if drawn, to fund a portion of the cash purchase price for the Storage Deluxe Acquisition until we complete arrangements for more permanent financing.

See "The Storage Deluxe Acquisition" and "Risk Factors — Risks Related to the Storage Deluxe Acquisition" for more information about the Storage Deluxe Acquisition, its financing and the risks related to the Storage Deluxe Acquisition and its financing.

We are currently in the process of finalizing our consolidated financial results for the three and nine months ended September 30, 2011. Based on preliminary unaudited information for the three and nine months ended September 30, 2011, we expect:

These preliminary results do not reflect the impact of the pending Storage Deluxe Acquisition and are subject to change.

FFO is a widely used performance measure for real estate companies and is provided here as a supplemental measure of operating performance. We calculate FFO in accordance with the best practices described in the April 2002 National Policy Bulletin of the National Association of Real Estate Investment Trusts (the "White Paper"). The White Paper defines FFO as net income (computed in accordance with GAAP), excluding gains (or losses) from sales of property, plus depreciation and amortization, and after adjustments for unconsolidated partnerships and joint ventures.

Management uses FFO as a key performance indicator in evaluating the operations of our facilities. Given the nature of our business as a real estate owner and operator, we consider FFO a key measure of our operating performance that is not specifically defined by accounting principles generally accepted in the United States. We believe that FFO is useful to management and investors as a starting point in measuring its operational performance because it excludes various items included in net income that do not relate to or are not indicative of our operating performance such as gains (or losses) from sales of property and depreciation, which can make periodic and peer analyses of operating

performance more difficult. FFO should not be considered as an alternative to net income (determined in accordance with GAAP) as an indicator of our financial performance, is not an alternative to cash flow from operating activities (determined in accordance with GAAP) as a measure of our liquidity, and is not indicative of funds available to fund our cash needs, including its ability to make distributions.

The following table presents our reconciliation of estimated FFO to our estimated earnings per diluted share:

Reconciliation of estimated FFO per diluted share to estimated earnings per diluted share	Range

Estimated earnings per diluted share allocated to common shareholders	$	0.06		–	$	0.07
Plus: estimated real estate depreciation and amortization		0.16		–		0.16
Less: estimated gains on sale of real estate		(0.04	)	–		(0.04	)
Less: estimated non-controlling interests in subsidiaries' share of FFO		(0.01	)	–		(0.01	)

Estimated FFO per diluted share	$	0.17		–	$	0.18

We calculate same-store revenues and same-store property operating expenses as the total continuing revenues and property operating expenses of facilities owned and operated on a stabilized basis throughout both of the periods presented. Same-store NOI is calculated as same-store revenues less same-store operating expenses. Same-store NOI also can be calculated by adding back to net income (loss): interest expense on loans, loan procurement amortization expense, loan procurement amortization expense — early repayment of debt, acquisition related costs, equity in earnings of real estate entities, amounts attributable to noncontrolling interests, other expense, depreciation and amortization expense, general and administrative expense, and deducting from net income: income from discontinued operations, gains on disposition of discontinued operations, other income, and interest income. NOI is not a measure of performance calculated in accordance with GAAP.

Management uses same-store revenues, same-store operating expenses and same-store NOI as a measure of operating performance at our facilities, and for all of our facilities in the aggregate. Same-store NOI should not be considered as a substitute for operating income, net income, cash flows provided by operating, investing and financing activities, or other income statement or cash flow statement data prepared in accordance with GAAP.

We consider our same-store portfolio to consist of only those facilities owned, and operated on a stabilized basis, at the beginning and at the end of the applicable periods presented. Same-store results are considered to be useful to investors in evaluating our performance as they provide information relating to changes in facility-level operating performance without taking into account the effects of acquisitions, developments or dispositions.

The preliminary financial data included above has been prepared by us, and our independent registered public accounting firm has not audited, reviewed, compiled or performed any procedures with respect to such information. Our independent registered public accounting firm is in the process of conducting its review of our financial statements for the three and nine months ended September 30, 2011. Such review could result in changes to the preliminary results indicated above. No assurance can be made that our actual results for the three and nine months ended September 30, 2011 will be consistent with the foregoing estimates.

The foregoing information constitutes forward looking statements. Please refer to the section entitled "Forward-Looking Statements" in this prospectus supplement.


Issuer		CubeSmart.
Securities Offered		17,000,000 common shares (19,550,000 shares if the underwriters exercise their option to purchase 2,550,000 additional shares in full).
Common Shares Outstanding as of October 21, 2011		99,565,406 shares.
Common Shares to be Outstanding Upon Completion of this Offering		116,565,406 shares.(1)
Use of Proceeds		We estimate that the net proceeds of this offering, after deducting the underwriting discount and other estimated offering expenses payable by us, will be approximately $ million (or approximately $ million if the underwriters exercise their option to purchase additional shares in full). We intend to contribute the net proceeds of this offering to the Operating Partnership. The Operating Partnership intends to use the net proceeds from this offering to pay a portion of the cash purchase price of the Storage Deluxe Acquisition. See "The Storage Deluxe Acquisition" and "Use of Proceeds" in this prospectus supplement.
		Prior to the closing of the Storage Deluxe Acquisition, we may hold the net proceeds from this offering in cash or short-term investments. In the event that we do not consummate the Storage Deluxe Acquisition, the Operating Partnership intends to use the proceeds for general business purposes, including other acquisitions, joint ventures or repayment of indebtedness.
New York Stock Exchange Symbol		"CUBE."
Restrictions or Ownership and Transfer		Our Declaration of Trust limits to 5.0% (in value or number of shares, whichever is more restrictive) the percentage ownership of our common shares by any one person or group affiliated persons, subject to certain exceptions. Our board of trustees may, in its sole discretion, exempt a person from the 5.0% ownership limit under certain circumstances.
Risk Factors		See "Risk Factors" beginning on page S-7 of this prospectus supplement and beginning on page 10 of our Annual Report on Form 10-K for the year ended December 31, 2010, to read about certain risks you should consider before making an investment in our common shares.

(1): Does not include (i) 5,248,218 common shares underlying an aggregate of 5,248,218 options that were granted pursuant to the U-Store-It Trust 2004 Equity Incentive Plan and the Amended and Restated U-Store-It Trust 2007 Equity Incentive Plan, or the Equity Incentive Plans, (ii) 4,362,320 common shares reserved for future grants of stock options (or other similar equity instruments) under the Equity Incentive Plans, (iii) 4,729,136 common shares reserved for redemption of units in the Operating Partnership and (iv) 2,550,000 common shares issuable to the underwriters if they exercise their option to purchase 2,550,000 additional shares in full.

Investing in our common shares involves a high degree of risk. You should carefully consider the risk factors incorporated by reference to our most recent Annual Report on Form 10-K, our subsequent Quarterly Reports on Form 10-Q and the other information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus, as updated by our subsequent filings under the Exchange Act. The occurrence of any of these risks might cause you to lose all or part of your investment in the offered shares. Please also refer to the section above entitled "Forward Looking Statements."

We have not established a minimum distribution payment level and we may be unable to generate sufficient cash flows from our operations to make distributions to our shareholders at any time in the future.

Historically, we have paid quarterly distributions to our shareholders, and we intend to pay quarterly distributions and to make distributions to our shareholders in amounts such that all or substantially all of our taxable income in each year, subject to certain adjustments, is distributed. This, along with other factors, should enable us to qualify for the tax benefits accorded to a REIT under the Internal Revenue Code. We have not established a minimum distribution payment level and all future distributions will be made at the discretion of our board of trustees. Our ability to make distributions to our shareholders may be adversely affected by the risk factors described in this prospectus supplement and in our Annual Report on Form 10-K for the year ended December 31, 2010. We may not generate sufficient income to continue to make distributions to our shareholders at our current level.

We currently do not expect to use the net proceeds from this offering to make distributions to our shareholders. However, to the extent we do so, the amount of cash we have available to invest in properties or for other purposes would be reduced. Our board of trustees has the sole discretion to determine the timing, form and amount of any distributions to our shareholders. Our board of trustees will make determinations regarding distributions based upon, among other factors, our financial performance, debt service obligations, debt covenants and capital expenditure requirements. Among the factors that could impair our ability to make distributions to our shareholders are:

As a result, no assurance can be given that we will be able to continue to make distributions to our shareholders at any time in the future or that the level of any distributions we do make to our shareholders will increase or even be maintained over time, any of which could materially and adversely affect the market price of our common shares.

In addition, distributions that we make to our shareholders generally will be taxable to our shareholders as ordinary income. However, a portion of our distributions may be designated by us as long-term capital gains to the extent that they are attributable to capital gain income recognized by us or may constitute a return of capital to the extent that they exceed our current and accumulated earnings and profits as determined for tax purposes. A return of capital is not taxable, but has the effect of reducing the adjusted tax basis of a shareholder's investment in our common shares.

Common shares eligible for future sale may adversely affect the prevailing market prices for our common shares.

We cannot predict the effect, if any, of future sales of common shares, or the availability of common shares for future sale, on the market price of our common shares. Sales of substantial amounts

of common shares (including shares issued to our trustees and officers), or the perception that these sales could occur, may adversely affect prevailing market prices for our common shares.

We, our executive officers and our trustees have agreed that, for a period of 60 days after the date of this prospectus supplement, we will not directly or indirectly, without the prior written consent of Wells Fargo sell or otherwise dispose of any common shares, subject to certain exceptions. In addition, Wells Fargo, at any time, may release all or a portion of the common shares subject to the foregoing lock-up provisions. If the restrictions under such agreements are waived, the affected common shares may be available for sale into the market, which could reduce the market price for our common shares.

We also may issue from time to time additional common shares or limited partnership interests in the Operating Partnership that are exchangeable for common shares in connection with the acquisition of properties and we may grant demand or piggyback registration rights in connection with these issuances. Sales of substantial amounts of our common shares or the perception that these sales could occur may adversely affect the prevailing market price for our common shares or may impair our ability to raise capital through a sale of additional equity securities.

The market price of our common shares may be volatile due to numerous circumstances beyond our control.

The trading prices of equity securities issued by REITs historically have been affected by changes in market interest rates. One of the factors that may influence the price of our common shares is the annual yield from distributions on our common shares as compared to yields on other financial instruments. An increase in market interest rates, which may lead prospective purchasers of our common shares to demand a higher annual yield, or a decrease in our distributions to shareholders, could reduce the market price of our common shares.

Other factors that could affect the market price of our common shares include the following:

Future offerings of debt or equity securities ranking senior to our common shares may limit our operating and financial flexibility and may adversely affect the market price of our common shares.

We may issue additional equity or debt securities from time to time in the future, including to fund a portion of the cash purchase price of the Storage Deluxe Acquisition. If we decide to issue debt or additional equity securities in the future ranking senior to our common shares or otherwise incur indebtedness, it is possible that these securities or indebtedness will be governed by an indenture or other instrument containing covenants restricting our operating flexibility and limiting our ability to make distributions to our common shareholders. Our credit facility contains provisions that, under certain circumstances, may prohibit us from making distributions on our common shares. Additionally, in the future we may issue additional securities that have rights, preferences and privileges, including with respect to distributions, more favorable than those of our common shares and may result in dilution to owners of our common shares. Because our decision to issue debt or equity securities or

otherwise incur indebtedness will depend on market conditions and other factors beyond our control, we cannot predict or estimate the amount, timing or nature of future issuances or financings, any of which could reduce the market price of our common shares and dilute the value of our common shares.

We may not complete the Storage Deluxe Acquisition and our shareholders may not realize any benefits from the proposed transaction.

The purchase agreement relating to the Storage Deluxe Acquisition contains closing conditions that need to be satisfied before the acquisition can be consummated. The satisfaction of most of these conditions is outside of our control, and we therefore cannot assure you that the acquisition will be consummated. These conditions include, among other things, satisfactory examination of the title to the properties, the ability to obtain title insurance, receipt of estoppels from ground lease lessors related to the leases to be assigned, execution of an additional lease at one facility with an affiliate of the seller, lender consents to the assumption of $88 million of secured fixed-rate debt and customary closing conditions, including the receipt of third party consents.

Moreover, in the event we are unable to complete Storage Deluxe Acquisition, we will have incurred significant legal, accounting and other transaction costs in connection with this acquisition without realizing the expected benefits. In addition, if we breach any of our representations or warranties or fail to perform any of our covenants in any material respect, we would be required to pay certain amounts held in escrow as liquidated damages.

We cannot assure you that the unaudited financial information provided by the sellers is accurate and we do not know with certainty the impact of these acquisitions on our operating results.

We cannot assure you that the unaudited financial information provided by the sellers as to the properties we are acquiring, and on which we based our purchase price, is accurate. Therefore, we are not able to determine with certainty the impact of the Storage Deluxe Acquisition on our operating results, interest and fixed charge coverage ratios and our expected returns from these properties.

We have not yet determined which financing alternatives we will use to fund the purchase price of the Storage Deluxe Acquisition and, depending on the types of financing alternatives we actually use, our indebtedness may increase substantially and our key financial indicators may be negatively affected.

We expect to finance a portion of the cash purchase price of the proposed Storage Deluxe Acquisition with the proceeds of this offering, and, subject to market conditions, fund the balance of the cash purchase price through other available sources of capital at the time of the transaction, which may include borrowings under the revolving portion of our unsecured credit facility, additional secured or unsecured financings, sales of preferred shares in public offerings or private placements or the bridge financing facilities described elsewhere in this prospectus supplement.

We cannot assure you that any or all of these financing sources will be available to us on favorable terms or at all, or which combination of funding sources we ultimately may use. If we are not able to fund the purchase price for the Storage Deluxe Acquisition we will lose all earnest money deposited in escrow. Depending on the financing arrangements, our indebtedness may increase substantially and our interest and fixed charge coverage ratios and other key financial indicators may be negatively affected.

In addition, any new indebtedness we incur to finance the Storage Deluxe Acquisition, such as the Storage Deluxe Acquisition Bridge Facility, will or may have variable interest rates. Increases in our debt and increases in interest rates on our variable rate indebtedness would increase our interest expense, which could adversely affect our cash flows and ability to make distributions to shareholders.

We may not be able to integrate successfully the new properties into our operations, which would adversely affect our results of operations and financial conditions.

The success of the Storage Deluxe Acquisition will depend, in part, on our ability to:

If we are unable to successfully integrate the acquired properties into our operations, our results of operations and financial condition may be adversely affected.

We may not be able to achieve the anticipated financial and operating results from the Storage Deluxe Acquisition, which could adversely affect our operating results.

We believe that the Storage Deluxe Acquisition will enhance our future financial performance, including our net earnings, net operating income and funds from operations. Our belief is subject to risks, uncertainties and other factors, many of which are beyond our control. In addition, our belief is based on certain assumptions, many of which are forward-looking and are set forth on page S-ii of this prospectus supplement, and are uncertain in nature. As a result, the actual performance of the properties we are proposing to acquire may differ materially from our anticipated results, which would negatively affect our operating results.

We may be responsible for unknown material liabilities associated with the Storage Deluxe properties which would adversely affect our business and for which we have limited recourse against the sellers.

We may be exposed to liabilities relating to the Storage Deluxe properties that we may have failed to discover prior to entering into the purchase agreement or that may arise after the acquisitions are completed. These liabilities may include liabilities that arise from litigation or non-compliance with environmental laws by prior owners for which we, as a successor owner, may be responsible. In the event that the sellers breach any of their representations or warranties, our sole and exclusive remedy is to pursue a claim against the sellers for actual damages which may not exceed $1 million, subject to a minimum of $10,000 and other limitations. Such limited recourse may not be sufficient or available to cover our liabilities in which case our results of operations may be adversely affected.

We estimate that the net proceeds from this offering, after deducting the underwriting discount and other estimated offering expenses payable by us, will be approximately $ million (or approximately $ million if the underwriters exercise their option to purchase additional shares in full). We intend to contribute the net proceeds of this offering of common shares to the Operating Partnership, in exchange for additional partnership interests in the Operating Partnership. We own our assets and conduct our operations through the Operating Partnership and its subsidiaries. We control the Operating Partnership as its sole general partner and, as of September 30, 2011, owned an approximate 95.4% interest in the Operating Partnership.

The Operating Partnership intends to use the net proceeds from this offering to pay a portion of the cash purchase price of the Storage Deluxe Acquisition. See "Summary — Recent Developments — The Storage Deluxe Properties Acquisition" in this prospectus supplement.

Prior to the closing of the Storage Deluxe Acquisition, we may hold the net proceeds from this offering in cash or short-term investments. In the event that we do not consummate the acquisition, the Operating Partnership intends to use the proceeds for general business purposes, including other acquisitions, joint ventures or repayment of indebtedness.

The following table sets forth our capitalization as of June 30, 2011 (1) on an actual basis and (2) on an as adjusted basis to give effect to the consummation of this offering. This table should be read in conjunction with our consolidated financial statements and the notes thereto incorporated by reference in this prospectus supplement.

		June 30, 2011

		Actual			As Adjusted(1)
		(in thousands) (unaudited)
Cash and Cash Equivalents:		$	1,845
Debt:
	Revolving credit facility		9,000
	Unsecured term loans		300,000
	Mortgage loan and notes payable		347,645
Non-controlling Interests in the Operating Partnership		$	49,789
Equity:
	Common Shares, par value $0.01 per share (200,000,000 shares authorized, 98,854,160 shares issued and outstanding at June 30, 2011)		989
	Preferred Shares, par value $0.01 per share (40,000,000 shares authorized, no shares issued and outstanding at June 30, 2011)		—
	Additional paid-in capital		1,028,640
	Accumulated other comprehensive loss		(113	)
	Accumulated deficit		(321,053	)
	Noncontrolling interest in subsidiaries		40,178
	Total equity	$	748,641

Total Capitalization		$	1,509,462

On October 24, 2011, the Operating Partnership entered into a purchase agreement to acquire a portfolio of 22 open and operating self-storage facilities from Storage Deluxe that contain an aggregate of approximately 1.6 million rentable square feet, including a recently opened 50,000 square foot property located in Bronx, NY. The properties are located in Brooklyn, NY, Woodhaven, NY, Jamaica, NY, Yorktown, NY, Tuckahoe, NY, New Rochelle, NY, Bronx, NY, Wilton, CT, Shelton, CT and Norristown, PA. The table below provides an overview of the portfolio of facilities that are the subject of the Storage Deluxe Acquisition as of June 30, 2011.

					Current

			Total Rentable Square Feet		Current
Market	# of Assets		Total Rentable Square Feet		Occupancy			Avg. Asking Rent PSF(1)		Avg. Realized Rent PSF(2)
Operating
Brooklyn		5		274,402		87.8	%	$	35.38	$	30.18
Queens		2		123,100		74.3	%		27.71		20.72
Bronx		8		742,805		85.9	%		33.17		28.19
Westchester		3		196,235		83.5	%		28.58		23.69
Connecticut		2		163,340		81.3	%		22.45		17.91
Pennsylvania		1		45,145		66.5	%		16.43		12.07

Operating Total / Wtd. Avg		21		1,545,027		84.0	%	$	30.92	$	26.07
Development
Bronx		1		50,225		NA			NA		NA

Combined Total / Wtd. Avg		22		1,595,252

The aggregate purchase price for the properties is approximately $560 million, comprised of approximately $472 million payable in cash and the assumption of approximately $88 million of existing fixed-rate debt. In connection with the execution of the purchase agreement, we are depositing approximately $45 million in escrow as earnest money. This escrow amount (excluding interest thereon) will be credited toward payment of the purchase price at closing of the acquisition. In addition to the purchase price, we expect to incur approximately $4.6 million of acquisition costs in connection with the Storage Deluxe Acquisition.

The consummation of the Storage Deluxe Acquisition is subject to satisfactory examination of the title to the properties, the ability to obtain title insurance, receipt of estoppels from ground lease lessors related to the leases to be assigned, execution of an additional lease at one facility with an affiliate of the seller, lenders consent to the assumption of $88 million of secured fixed-rate debt and customary closing conditions, including the receipt of third party consents. We cannot assure you that we will be able to complete the acquisition of these properties as anticipated or at all.

If the lenders do not consent to the assumption of the $88 million of secured fixed-rate debt on the properties by July 31, 2012, the sellers can terminate the agreement with respect to the second group of properties. We may also elect to terminate the agreement if certain title deficiencies are not remedied by the sellers. In the event that the sellers breach their obligations to consummate the acquisition in a material way, we may either (i) terminate the agreement, in which case we will be entitled to the return of the earnest money or (ii) specifically enforce the agreement within 30 days of the breach. In the event that the sellers breach any of their representations or warranties, our sole and exclusive remedy is to pursue a claim against the sellers within 30 days of closing for actual damages which may not exceed $1.0 million, subject to minimum damages of $10,000 and other limitations. We have the right to terminate the agreement if the sellers intentionally or willfully breach or default in certain of their obligations and the breach or default results in the failure of the lenders to approve the assumption of the $88 million of secured fixed-rate debt. Upon such termination we will be entitled to the return of a portion of the earnest money and $9.0 million as liquidated damages. We will have no right to terminate the agreement if any of the properties is damaged or destroyed by fire or other casualty. If we breach our representations and warranties or fail to comply with our covenants in any material respect, the sellers may terminate the agreement, in which case any remaining earnest money that has not been used in a prior closing will be paid to them as liquidated damages.

We expect to finance a portion of the cash purchase price for the Storage Deluxe Acquisition with the proceeds of this offering, as well as a combination of borrowings under the revolving portion of our unsecured credit facility, additional secured or unsecured financings, sales of preferred shares in public offerings or private placements or the bridge financing facilities described below. We are in the process of continuing to finalize these sources of financing and cannot assure you that any or all of these sources of financing will be available to us, on favorable terms or at all.

In order to ensure that financing will be available to consummate the Storage Deluxe Acquisition, we have received $300.0 million of combined bridge financing facilities from affiliates of Wells Fargo Securities, LLC. Under these facilities, an affiliate of Wells Fargo Securities, LLC has agreed to purchase, upon our request and subject to certain conditions, up to 8,000,000 shares (or $200.0 million in aggregate liquidation preference) of a new series of our cumulative redeemable preferred shares under our Preferred Equity Line at a price per share equal to $24.0875. Under our Storage Deluxe Acquisition Bridge Facility, another affiliate of Wells Fargo Securities, LLC has agreed to provide us with a new $100.0 million unsecured term loan facility, subject to certain conditions, including the absence of material adverse change, satisfactory due diligence, and the receipt of at least $175 million in equity capital. This facility will mature within six months but we will have the ability to extend it by an additional five years.

This term loan facility will be guaranteed by all our existing and future material subsidiaries and bears interest at variable rates. Other covenants, indemnification provisions and conditions precedent to borrowings under the term loan facility are substantially the same as those under our existing revolving credit facility.

Each of the Preferred Equity Line and Storage Deluxe Acquisition Bridge Facility are currently undrawn. The commitments under the Preferred Equity Line are available until March 31, 2012 and the commitments under the Storage Deluxe Acquisition Bridge Facility are available until April 30, 2012. We intend to use proceeds from the Preferred Equity Line or Storage Deluxe Acquisition Bridge Facility, if drawn, to fund a portion of the purchase price for the Storage Deluxe Acquisition until we complete arrangements for more permanent financing.

Wells Fargo Securities, LLC will receive a fee in connection with the Preferred Equity Line of up to 1.25% of the aggregate liquidation preference of the preferred shares that may be issued and affiliates of Wells Fargo Securities, LLC will receive customary fees and commissions in connection with the Storage Deluxe Acquisition Bridge Facility.

See "Risk Factors — Risks Related to the Storage Deluxe Acquisition" for more information about the risks related to the Storage Deluxe Acquisition and its financing.

Subject to the terms and conditions set forth in an underwriting agreement, we have agreed to sell to the underwriters named below, and the underwriters, for whom Wells Fargo Securities, LLC is acting as book running manager and representative, have severally agreed to purchase, the respective numbers of shares appearing opposite their names below:

All of the shares to be purchased by the underwriters will be purchased from us.

The underwriting agreement provides that the obligations of the several underwriters are subject to various conditions, including approval of legal matters by counsel. The common shares are offered by the underwriters, subject to prior sale, when, as and if issued to and accepted by them. The underwriters reserve the right to withdraw, cancel or modify the offer and to reject orders in whole or in part.

The underwriting agreement provides that the underwriters are obligated to purchase all of the common shares offered by this prospectus if any are purchased, other than those shares covered by the option to purchase additional common shares described below. If an underwriter defaults, the underwriting agreement provides that the purchase commitments of the non-defaulting underwriters may be increased or the underwriting agreement may be terminated.

We have granted a 30-day option to the underwriters to purchase a total of up to 2,550,000 additional common shares from us at the public offering price per share less the underwriting discounts and commissions per share, as set forth on the cover page of this prospectus, and less any dividends or distributions declared, paid or payable on the shares that the underwriters have agreed to purchase from us but that are not payable on such additional shares. If the underwriters exercise this option in whole or in part, then the underwriters will be severally committed, subject to the conditions described in the underwriting agreement, to purchase the additional common shares in proportion to their respective commitments set forth in the prior table.

Shares sold by the underwriters to the public will initially be offered at the public offering price set forth on the cover of this prospectus and to certain dealers at that price less a concession of not more than $ per share. After the initial offering, the public offering price and concession to dealers may be changed.

The following table summarizes the underwriting discounts and commissions and the proceeds, before expenses, payable to us, both on a per share basis and in total, assuming either no exercise or full exercise by the underwriters of their option to purchase additional shares:

We estimate that the expenses of this offering payable by us, not including underwriting discounts and commissions, will be approximately $ .

The underwriting agreement provides that we will indemnify the underwriters against specified liabilities, including liabilities under the Securities Act of 1933, as amended, or the Securities Act, or contribute to payments that the underwriters may be required to make in respect of those liabilities.

We and each of our trustees and executive officers have agreed, subject to certain exceptions described below, that, without the prior written consent of Wells Fargo Securities, LLC, we and they will not, subject to certain exception, during the period beginning on and including the date of this prospectus through and including the date that is the 60th day after the date of this prospectus, directly or indirectly:

whether any transaction described in the first or third bullet point above is to be settled by delivery of our common shares, other capital shares, other securities, in cash or otherwise, or publicly announce an intention to do any of the foregoing. Moreover, if:

the restrictions described in the immediately preceding sentence will continue to apply until the expiration of the 18-day period beginning on the date of issuance of the earnings release or the occurrence of the material news or material event, as the case may be, unless Wells Fargo Securities, LLC waives, in writing, that extension.

Notwithstanding the provisions set forth in the immediately preceding paragraph, we may, without the prior written consent of Wells Fargo Securities, LLC:

The restrictions of the lock-up agreements which our trustees and executive officers are party to do not apply to the following:

provided that (1) for all transfers described in the first two bullets above, the recipient enters into a lock-up agreement in a form satisfactory to Wells Fargo Securities, LLC no later than one business day before the transfer, (2) for transfers (a) by will, intestate succession or pursuant to certain trusts, any report required to be filed under specified sections of the Exchange Act will state the reason for the transfer and that the transfer was not for value, and (b) for all transfers described in the second bullet above, no report under specified sections of the Securities Act or Exchange Act is required to be filed during the period the above restrictions apply (as the same may be extended), and (3) for all transfers described in the first two bullets above, no other filing with the SEC, the Financial Industry Regulatory Authority or any securities exchange or other public report, filing or announcement is made in connection with the transfer.

Wells Fargo Securities, LLC may, in its sole discretion and at any time or from time to time, without notice, release all or any portion of the shares or other securities subject to the lock-up agreements. Any determination to release any shares or other securities subject to the lock-up agreements would be based on a number of factors at the time of determination, which may include the market price of the common shares, the liquidity of the trading market for the common shares, general market conditions, the number of shares or other securities proposed to be sold or otherwise transferred and the timing, purpose and terms of the proposed sale or other transfer.

Our common shares are listed on the New York Stock Exchange under the symbol "CUBE."

In order to facilitate this offering of our common shares, the underwriters may engage in transactions that stabilize, maintain or otherwise affect the market price of our common shares. Specifically, the underwriters may sell more common shares than they are obligated to purchase under the underwriting agreement, creating a short position. A short sale is covered if the short position is no greater than the number of common shares available for purchase by the underwriters under the option to purchase additional shares referred to above. The underwriters may close out a covered short sale by exercising the option to purchase additional shares or purchasing our common shares in the open market. In

determining the source of common shares to close out a covered short sale, the underwriters may consider, among other things, the market price of our common shares compared to the price payable under the option to purchase additional shares. The underwriters may also sell common shares in excess of the option to purchase additional shares, creating a naked short position. The underwriters must close out any naked short position by purchasing our common shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of our common shares in the open market after the date of pricing of this offering that could adversely affect investors who purchase in this offering.

As an additional means of facilitating this offering, the underwriters may bid for, and purchase, common shares in the open market to stabilize the price of our common shares, so long as stabilizing bids do not exceed a specified maximum. The underwriting syndicate may also reclaim selling concessions allowed to an underwriter or a dealer for distributing common shares in this offering if the underwriting syndicate repurchases previously distributed common shares to cover syndicate short positions or to stabilize the price of our common shares.

The foregoing transactions, if commenced, may raise or maintain the market price of our common shares above independent market levels or prevent or retard a decline in the market price of our common shares.

The foregoing transactions, if commenced, may be effected on the New York Stock Exchange or otherwise. Neither we nor any of the underwriters makes any representation that the underwriters will engage in any of these transactions and these transactions, if commenced, may be discontinued at any time without notice. Neither we nor any of the underwriters makes any representation or prediction as to the direction or magnitude of the effect that the transactions described above, if commenced, may have on the market price of our common shares.

Some of the underwriters and/or their respective affiliates have in the past provided and all of the underwriters may in the future provide various financial advisory, investment banking, commercial banking and other financial services to us, for which they have received and in the future may receive compensation.

Affiliates of Wells Fargo Securities, LLC and certain of the other underwriters act as lenders and/or agents under our $250.0 million unsecured revolving credit facility, our $200.0 million unsecured term loan and our $200.0 million term loan facility. As of September 30, 2011, we had aggregate outstanding indebtedness of $300.0 million under the unsecured term loan and the term loan facility. Certain affiliates of Wells Fargo Securities, LLC and certain of the other underwriters also act as lenders under mortgages on certain of our properties. In addition, in order to ensure that financing will be available to consummate the Storage Deluxe Acquisition, we have received $300.0 million of combined bridge financing commitments from affiliates of Wells Fargo Securities, LLC. We expect to use proceeds from the Preferred Equity Line or Storage Deluxe Acquisition Bridge Facility, if drawn, to fund a portion of the cash purchase price for the Storage Deluxe Acquisition. See "The Storage Deluxe Acquisition — Financing for the Storage Deluxe Acquisition." Wells Fargo Securities, LLC will receive a fee in connection with the Preferred Equity Line of up to 1.25% of the aggregate liquidation preference of the preferred shares that may be issued and affiliates of Wells Fargo Securities, LLC will receive customary fees and commissions in connection with the Storage Deluxe Acquisition Bridge Facility.

No action has been or will be taken in any jurisdiction (except in the United States) that would permit a public offering of the common shares, or the possession, circulation or distribution of this prospectus or any other material relating to us or the common shares in any jurisdiction where action for that purpose is required. Accordingly, the common shares may not be offered or sold, directly or

indirectly, and neither of this prospectus nor any other offering material or advertisements in connection with the common shares may be distributed or published, in or from any country or jurisdiction except in compliance with any applicable rules and regulations of any such country or jurisdiction.

Each of the underwriters may arrange to sell common shares offered by this prospectus in certain jurisdictions outside the United States, either directly or through affiliates, where they are permitted to do so. In that regard, Wells Fargo Securities, LLC may arrange to sell shares in certain jurisdictions through an affiliate, Wells Fargo Securities International Limited, or WFSIL. WFSIL is a wholly-owned indirect subsidiary of Wells Fargo & Company and an affiliate of Wells Fargo Securities, LLC. WFSIL is a U.K. incorporated investment firm regulated by the Financial Services Authority. Wells Fargo Securities is the trade name for certain corporate and investment banking services of Wells Fargo & Company and its affiliates, including Wells Fargo Securities, LLC and WFSIL.

In relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a "Relevant Member State") an offer to the public of any common shares which are the subject of the offering contemplated by this prospectus (the "Shares") may not be made in that Relevant Member State except that an offer to the public in that Relevant Member State of any Shares may be made at any time under the following exemptions under the Prospectus Directive, if they have been implemented in that Relevant Member State:

provided that no such offer of Shares shall result in a requirement for the publication by us or any underwriter of a prospectus pursuant to Article 3 of the Prospectus Directive.

For the purposes of this provision, the expression an "offer to the public" in relation to any Shares in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and any Shares to be offered so as to enable an investor to decide to purchase any Shares, as the same may be varied in that Member State by any measure implementing the Prospectus Directive in that Member State; the expression "Prospectus Directive" means Directive 2003/71/EC (and amendments thereto, including the 2010 PD Amending Directive, to the extent implemented in the Relevant Member State) and includes any relevant implementing measure in each Relevant Member State; and the expression "2010 PD Amending Directive" means Directive 2010/73/EU.

The common shares may be offered in the United Kingdom only where each underwriter:

This prospectus and any other material in relation to the shares is only being distributed to, and is only directed at, persons in the United Kingdom that are qualified investors within the meaning of Article 2(1)(e) of the Prospective Directive ("qualified investors") (i) that also have professional experience in matters relating to investments falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended, or the Order, (ii) who fall within Article 49(2)(a) to (d) of the Order or (iii) to whom it may otherwise lawfully be communicated (all such persons together being referred to as "relevant persons"). The shares are only available to, and any invitation, offer or agreement to purchase or otherwise acquire such shares will be engaged in only with, relevant persons. Any person in the United Kingdom that is not a relevant person should not act or rely on this prospectus or any of its contents.

This document has not been prepared in accordance with the requirements for a securities or sales prospectus under the German Securities Prospectus Act (Wertpapierprospektgesetz), the German Sales Prospectus Act (Verkaufsprospektgesetz), or the German Investment Act (Investmentgesetz). Neither the German Federal Financial Services Supervisory Authority (Bundesanstalt fur Finanzdienstleistungsaufsicht — BaFin) nor any other German authority has been notified of the intention to distribute the common shares in Germany. Consequently, the common shares may not be distributed in Germany by way of public offering, public advertisement or in any similar manner AND THIS DOCUMENT AND ANY OTHER DOCUMENT RELATING TO THE OFFERING, AS WELL AS INFORMATION OR STATEMENTS CONTAINED HEREIN OR THEREIN, MAY NOT BE SUPPLIED TO THE PUBLIC IN GERMANY OR USED IN CONNECTION WITH ANY OFFER FOR SUBSCRIPTION OF THE SHARES TO THE PUBLIC IN GERMANY OR ANY OTHER MEANS OF PUBLIC MARKETING. The common shares are being offered and sold in Germany only to qualified investors which are referred to in Section 3, paragraph 2 no. 1, in connection with Section 2, no. 6, of the German Securities Prospectus Act. This document is strictly for use of the person who has received it. It may not be forwarded to other persons or published in Germany.

This document does not constitute a prospectus within the meaning of Art. 652a of the Swiss Code of Obligations. The common shares may not be sold directly or indirectly in or into Switzerland except in a manner which will not result in a public offering within the meaning of the Swiss Code of Obligations. Neither this document nor any other offering materials relating to the common shares may be distributed, published or otherwise made available in Switzerland except in a manner which will not constitute a public offer of the common shares in Switzerland.

Certain legal matters in connection with this offering will be passed upon for us by Pepper Hamilton LLP. Certain legal matters in connection with this offering will be passed upon for the underwriters by Hunton & Williams LLP.

The consolidated financial statements and financial statement schedule of CubeSmart (formerly U-Store-It Trust) as of December 31, 2010 and 2009 and for each of the years in the three-year period ended December 31, 2010 and management's assessment of the effectiveness of internal control over financial reporting as of December 31, 2010 have been incorporated by reference herein in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

We incorporate information into this prospectus supplement and the accompanying prospectus by reference, which means that we disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus supplement and the accompanying prospectus, except to the extent superseded by information contained herein or by information contained in documents filed with the SEC after the date of this prospectus supplement and the accompanying prospectus. This prospectus supplement and the accompanying prospectus incorporate by reference the documents set forth below that have been previously filed with the SEC (other than, in each case, documents or information deemed to have been "furnished" and not "filed" in accordance with SEC rules):

We also incorporate by reference into this prospectus supplement and the accompanying prospectus additional documents that we may file with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act, from the date of this prospectus supplement until all of the securities offered by this prospectus supplement have been sold or we otherwise terminate the offering of these securities; provided, however, that we are not incorporating by reference any additional documents or information "furnished" and not "filed" with the SEC. You may obtain copies of any of these filings by contacting us at the following address and phone number or by contacting the SEC or NYSE as described above. Documents incorporated by reference are available from us without charge, excluding all exhibits unless an exhibit has been specifically incorporated by reference into this prospectus supplement or the accompanying prospectus, by requesting them in writing, by telephone or via the Internet at:

CubeSmart
Attention: Investor Relations
460 East Swedesford Road, Suite 3000
Wayne, PA 19087
Phone: (610) 293-5700
Internet Website: www.cubesmart.com

The information contained on our website does not constitute a part of this prospectus supplement or the accompanying prospectus, and our website address supplied above is intended to be an inactive textual reference only and not an active hyperlink to our website.

We are subject to the informational requirements of the Exchange Act. Accordingly, we file current, quarterly and annual reports, proxy statements and other information with the SEC. You may read and copy these reports, proxy statements and other information at the SEC's Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. Please call 1-800-SEC-0330 for further information on the operation of the SEC's Public Reference Room. Our SEC filings also are available to the public at the Internet website maintained by the SEC at www.sec.gov and from commercial document retrieval services.

We also make available free of charge through our website our filings with the SEC, including our annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act, definitive proxy statements and Section 16 reports on Forms 3, 4 and 5, as soon as reasonably practicable after we electronically file such reports or amendments with, or furnish them to, the SEC. Our Internet website address is www.cubesmart.com. The information located on, or hyperlinked or otherwise connected to, our website is not, and shall not be deemed to be, a part of this prospectus supplement or incorporated into any other filings that we make with the SEC. You may also inspect the information that we file with the NYSE, at the offices of the NYSE located at 20 Broad Street, New York, New York 10005.

We have filed with the SEC a registration statement on Form S-3 (Registration File No. 333-176885) covering the common shares offered by this prospectus supplement and the accompanying prospectus. You should be aware that this prospectus supplement and related prospectus do not contain all of the information contained or incorporated by reference in that registration statement and its exhibits and schedules. You may inspect and obtain the registration statement, including exhibits, schedules, reports and other information that we have filed with the SEC, as described in the preceding paragraph. Statements contained in this prospectus supplement concerning the contents of any document we refer you to are not necessarily complete and in each instance we refer you to the applicable document filed with the SEC for more complete information.

CubeSmart may from time to time offer, in one or more classes or series, separately or together, and in amounts, at prices and on terms to be set forth in one or more supplements to this prospectus, the following securities:

CubeSmart, L.P. may from time to time offer, in one or more classes or series, separately or together, and in amounts, at prices and on terms to be set forth in one or more supplements to this prospectus, its debt securities. CubeSmart will unconditionally guarantee the payment obligations of the debt securities of CubeSmart, L.P.

We refer to the common shares, preferred shares, depositary shares, subscription rights, warrants and guarantees of CubeSmart, together with the debt securities of CubeSmart, L.P. collectively as the "securities."

The common shares of CubeSmart are listed on the New York Stock Exchange, or NYSE. On September 19, 2011, the listing symbol of CubeSmart's common shares on the NYSE will change from "YSI" to "CUBE."

Investing in the securities involves risks that are described on page 6 of this prospectus. You should carefully read and consider this prospectus, the applicable prospectus supplement and the risk factors included in the applicable prospectus supplement and/or in our periodic reports and other information that we file with the Securities and Exchange Commission before investing in the securities.

Neither the Securities and Exchange Commission nor any state securities regulators have approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.


ABOUT THIS PROSPECTUS			1
WHERE YOU CAN FIND MORE INFORMATION			1
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE			2
FORWARD-LOOKING STATEMENTS			4
CUBESMART AND THE OPERATING PARTNERSHIP			5
RISK FACTORS			6
USE OF PROCEEDS			6
RATIO OF EARNINGS TO FIXED CHARGES AND RATIO OF EARNINGS TO COMBINED FIXED CHARGES AND PREFERENCE DIVIDENDS			7
DESCRIPTION OF CUBESMART'S CAPITAL SHARES			8
DESCRIPTION OF DEPOSITARY SHARES			16
DESCRIPTION OF SUBSCRIPTION RIGHTS			19
DESCRIPTION OF WARRANTS			20
DESCRIPTION OF THE DEBT SECURITIES			22
MATERIAL FEDERAL INCOME TAX CONSIDERATIONS			38
PLAN OF DISTRIBUTION			68
LEGAL MATTERS			70
EXPERTS			70

You should rely only on the information provided or incorporated by reference into this prospectus or any applicable prospectus supplement. We have not authorized anyone to provide you with different or additional information. This prospectus does not constitute an offer to sell or a solicitation of an offer to buy by anyone in any jurisdiction in which such offer to sell is not authorized, or in which the person is not qualified to do so or to any person to whom it is unlawful to make such offer or solicitation. You should not assume that the information included in this prospectus, any prospectus supplement, or the documents incorporated by reference herein or therein is accurate as of any date other than the date of this prospectus, any prospectus supplement or incorporated document, as applicable. Our business, financial condition, results of operations and prospects may have changed since those dates.

This prospectus is part of a universal shelf registration statement on Form S-3 that we filed with the Securities and Exchange Commission, or the SEC, under the Securities Act of 1933, as amended, or the Securities Act. To the extent required for any offer and sale, a prospectus supplement will set forth the type and number of securities being offered, the offering price, the names of any underwriters, dealers, brokers or agents and the applicable sales commission or discount. The prospectus supplement may also add, update or change information contained in this prospectus. You should read carefully the entire prospectus and any prospectus supplement, as well as the documents incorporated by reference into this prospectus and/or any prospectus supplement, before making an investment decision.

This prospectus and any accompanying prospectus supplement do not contain all of the information included in the registration statement. For further information, we refer you to the registration statement, including the exhibits. Statements contained in this prospectus and any accompanying prospectus supplement about the provisions or contents of any agreement or other document are not necessarily complete. If the rules and regulations of the SEC require that such agreement or document be filed as an exhibit to the registration statement, please see such agreement or document for a complete description of these matters.

As used in this prospectus and the registration statement on Form S-3 of which this prospectus is a part, unless the context otherwise requires, references to "CubeSmart" refer to CubeSmart, a Maryland real estate investment trust, or "REIT"; references to the "Operating Partnership" refer to CubeSmart, L.P., a Delaware limited partnership; and references to "we," "us," "our" or similar expressions refer collectively to CubeSmart and its consolidated subsidiaries (including the Operating Partnership).

We are subject to the informational requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act. Accordingly, we file current, quarterly and annual reports, proxy statements and other information with the SEC. You may read and copy these reports, proxy statements and other information at the SEC's Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. Please call 1-800-SEC-0330 for further information on the operation of the SEC's Public Reference Room. Our SEC filings also are available to the public at the Internet website maintained by the SEC at www.sec.gov and from commercial document retrieval services.

We also make available free of charge through our website the filings made by CubeSmart and the Operating Partnership with the SEC, including the Operating Partnership's Registration Statement on Form 10, as amended, and CubeSmart's annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act, definitive proxy statements and Section 16 reports on Forms 3, 4 and 5, as soon as reasonably practicable after we electronically file such reports or amendments with, or furnish them to, the SEC. Our Internet website address is www.cubesmart.com. The information located on, or hyperlinked or otherwise connected to, our website is not, and shall not be deemed to be, a part of this prospectus or incorporated into any other filings that we make with the SEC. You may also inspect the information that we file with the NYSE, at the offices of the NYSE located at 20 Broad Street, New York, New York 10005.

We incorporate information into this prospectus by reference, which means that we disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, except to the extent superseded by information contained herein or by information contained in documents filed with the SEC after the date of this prospectus. This prospectus incorporates by reference the documents set forth below that have been previously filed with the SEC (other than, in each case, documents or information deemed to have been "furnished" and not "filed" in accordance with SEC rules):

We also incorporate by reference into this prospectus additional documents that we may file with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act, from the date of this prospectus until all of the securities offered by this prospectus have been sold or we otherwise terminate the offering of these securities; provided, however, that we are not incorporating by reference any additional documents or information "furnished" and not "filed" with the SEC. You may obtain copies of any of these filings by contacting us at the following address and phone number or by contacting the SEC or NYSE as described above. Documents incorporated by reference are available from us without charge, excluding all exhibits unless an exhibit has been specifically incorporated by reference into this prospectus, by requesting them in writing, by telephone or via the Internet at:

CubeSmart
Attention: Investor Relations
460 East Swedesford Road, Suite 3000
Wayne, PA 19087
Phone: (610) 293-5700
Internet Website: www.cubesmart.com

The information contained on our website does not constitute a part of this prospectus, and our website address supplied above is intended to be an inactive textual reference only and not an active hyperlink to our website.

You should rely only on the information contained or incorporated by reference in this prospectus, the prospectus supplement, any free writing prospectus that we authorize and any pricing supplement. We have not authorized any person, including any salesman or broker, to provide information other than that provided in this prospectus, any applicable prospectus supplement, any free writing prospectus that we authorize or any pricing supplement. We have not authorized anyone to provide you with different information. We do not take responsibility for, and can provide no assurance as to the reliability of, any information that others may give you. We are not making an offer of the securities in

any jurisdiction where the offer is not permitted. You should assume that the information in this prospectus, any applicable prospectus supplement, any free writing prospectus that we authorize and any pricing supplement is accurate only as of the date on its cover page and that any information we have incorporated by reference is accurate only as of the date of such document incorporated by reference.

Any statement contained in a document incorporated or deemed to be incorporated by reference into this prospectus will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus, any prospectus supplement, or any other subsequently filed document that is deemed to be incorporated by reference into this prospectus modifies or supersedes the statement. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to constitute a part of this prospectus.

This prospectus and any accompanying prospectus supplement, together with other documents and information incorporated by reference into this prospectus, contain certain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). Such statements are based on assumptions and expectations that may not be realized and are inherently subject to risks, uncertainties and other factors, many of which cannot be predicted with accuracy and some of which might not even be anticipated. Although we believe the expectations reflected in these forward-looking statements are based on reasonable assumptions, future events and actual results, performance, transactions or achievements, financial and otherwise, may differ materially from the results, performance, transactions or achievements expressed or implied by the forward-looking statements contained in or contemplated by this prospectus or any prospectus supplement. Any forward-looking statements should be considered in light of the risks and uncertainties referred to in Item 1A. "Risk Factors" in CubeSmart's Annual Report on Form 10-K for the year ended December 31, 2010 and in Item 1A. "Risk Factors" in the Operating Partnership's Registration Statement on Form 10, as amended. The most significant of these risks, uncertainties and other factors that might cause such differences include, but are not limited to:

In light of these uncertainties and risks, prospective investors are cautioned not to place undue reliance on these forward-looking statements. Except with respect to such material changes to our risk factors as may be reflected from time to time in our quarterly filings or as otherwise required by law, we are under no obligation to, and expressly disclaim any obligation to, update or revise any forward-looking statements included or incorporated by reference in this prospectus or any accompanying prospectus supplement, whether as a result of new information, future events or otherwise. Because of the factors referred to above, the future events discussed in or incorporated by reference in this prospectus or any accompanying prospectus supplement may not occur and actual results, performance or achievement could differ materially from that anticipated or implied in the forward-looking statements.

CubeSmart is a self-administered and self-managed real estate investment trust, or REIT, focused primarily on the ownership, operation, acquisition and development of self-storage facilities in the United States. CubeSmart was organized and commenced operations in 2004 as a Maryland REIT. The Operating Partnership was formed and commenced operations in 1996 as a Delaware limited partnership. Effective September 14, 2011, CubeSmart changed its name from "U-Store-It Trust" and the Operating Partnership changed its name from "U-Store-It, L.P." to "CubeSmart, L.P."

CubeSmart owns its assets, and conducts its operations, through the Operating Partnership. CubeSmart controls the Operating Partnership as its sole general partner and, as of June 30, 2011, CubeSmart owned an approximately 95.4% interest in the Operating Partnership. The Operating Partnership has been engaged in virtually all aspects of the self-storage business, including the development, acquisition, ownership and operation of self-storage facilities.

Our self-storage facilities are designed to offer affordable and easily-accessible storage space for our residential and commercial customers. Our customers rent storage units for their exclusive use, typically on a month-to-month basis. Additionally, some of our facilities offer outside storage areas for vehicles and boats. Our facilities are designed to accommodate both residential and commercial customers, with features such as security systems and wide aisles and load-bearing capabilities for large truck access. All of our facilities have an on-site manager during business hours, and many have a manager who resides in an apartment at the facility. Our customers can access their storage units during business hours, and some of our facilities provide customers with 24-hour access through computer controlled access systems. Our goal is to provide customers with the highest standard of facilities and service in the industry. To that end, as of June 30, 2011, a majority of our facilities included climate controlled units.

Our executive offices are located at 460 East Swedesford Road, Suite 3000, Wayne, PA 19087 and our telephone number is (610) 293-5700.

Investing in our securities involves risks. You should carefully consider the risk factors incorporated by reference to CubeSmart's most recent Annual Report on Form 10-K, CubeSmart's subsequent Quarterly Reports on Form 10-Q, the Operating Partnership's Registration Statement on Form 10, as amended, and the other information contained or incorporated by reference in this prospectus, as updated by our subsequent filings under the Exchange Act, and the risk factors and other information contained in the applicable prospectus supplement before acquiring any of such securities. The occurrence of any of these risks might cause you to lose all or part of your investment in the offered securities. Please also refer to the section above entitled "Forward-Looking Statements."

Unless otherwise indicated in the applicable prospectus supplement, CubeSmart will contribute or otherwise transfer the net proceeds of any sale of securities to the Operating Partnership in exchange for additional partnership interests in the Operating Partnership, the economic terms of which will be substantially identical to those of the securities sold.

Unless otherwise indicated in the applicable prospectus supplement, the Operating Partnership will use those net proceeds and any net proceeds from any sale of its debt securities for general business purposes, including, without limitation, repayment of outstanding debt, acquisitions, developments, capital expenditures, working capital and other general corporate purposes.

RATIO OF EARNINGS TO FIXED CHARGES AND RATIO OF EARNINGS TO COMBINED FIXED CHARGES AND PREFERENCE DIVIDENDS

The following table sets forth the Operating Partnership's ratios of earnings to fixed charges for the periods indicated.

For the purpose of calculating the ratio of earnings to fixed charges, earnings consist of income (loss) from continuing operations, plus fixed charges less capitalized interest. Fixed charges consist of interest expense, capitalized interest, amortized premiums, discounts and capitalized expenses relating to debt and an estimate of the interest component of rent expense.

The following table sets forth CubeSmart's ratios of earnings to combined fixed charges and preference dividends for the periods indicated.

For the purpose of calculating the ratio of earnings to combined fixed charges and preference dividends, earnings consist of income (loss) from continuing operations, plus fixed charges less capitalized interest. Fixed charges consist of interest expense, capitalized interest, amortized premiums, discounts and capitalized expenses relating to debt and an estimate of the interest component of rent expense. Preference dividends includes income allocated to holders of CubeSmart's preferred shares.

The following description of our capital shares, together with the additional information we include in any applicable prospectus supplement, summarizes the material terms and provisions of the capital shares that may be offered under this prospectus. For the complete terms of our capital shares, please refer to our declaration of trust and bylaws that are filed as exhibits to our reports incorporated by reference into the registration statement of which this prospectus is a part. See "Where You Can Find More Information."

CubeSmart's declaration of trust provides that CubeSmart may issue up to 200,000,000 common shares of beneficial interest, par value $0.01 per share. As of September 13, 2011, there were 99,583,259 common shares issued and outstanding.

Both Maryland statutory law governing real estate investment trusts formed under Maryland law, which we refer to as the Maryland REIT Law, and CubeSmart's declaration of trust provide that none of its shareholders will be personally liable, by reason of status as a shareholder, for any of its obligations.

Subject to the provisions of CubeSmart's declaration of trust regarding restrictions on the transfer and ownership of shares of beneficial interest, each outstanding common share entitles the holder to one vote on all matters submitted to a vote of shareholders, including the election of trustees, and, except as provided with respect to any other class or series of shares of beneficial interest that CubeSmart may issue, the holders of such common shares will possess exclusive voting power. There is no cumulative voting in the election of trustees. As a result, the holders of a majority of the outstanding common shares, voting as a single class, can elect all of the trustees then standing for election. CubeSmart's bylaws provide that a plurality of the votes case at a meeting of shareholders duly called at which a quorum is present is sufficient to elect a trustee and that a majority of the votes cast at a meeting of shareholders duly called at which a quorum is present is sufficient to approve any other matter which may properly come before the meeting, unless a higher vote is required under CubeSmart's bylaws, CubeSmart's declaration of trust or applicable statute.

Under the Maryland REIT law, a Maryland REIT generally cannot amend its declaration of trust or merge with another entity without the affirmative vote of shareholders holding at least two-thirds of the shares entitled to vote on the matter unless a lesser percentage (but not less than a majority of all the votes entitled to be cast on the matter) is set forth in the REIT's declaration of trust. Our declaration of trust provides that amendments to the declaration of trust and our merger with another entity may be approved by the affirmative vote of the holders of not less than a majority of all votes entitled to be cast on the matter. Under the Maryland REIT law and CubeSmart's declaration of trust, its trustees will be permitted to amend the declaration of trust from time to time to maintain our qualification as a REIT under the Internal Revenue Code of 1986, as amended, or the Code, and under the Maryland REIT law, without the affirmative vote or written consent of the shareholders.

All common shares offered by this prospectus will be duly authorized, fully paid and nonassessable. Holders of CubeSmart's common shares are entitled to receive dividends and distributions when authorized by our board of trustees, and declared by CubeSmart out of assets legally available for the payment of dividends or distributions. They also are entitled to share ratably in CubeSmart's assets legally available for distribution to its shareholders in the event of CubeSmart's liquidation, dissolution or winding up, after payment of or adequate provision for all of its known debts and liabilities. These rights are subject to the preferential rights of any other class or series of CubeSmart's shares and to the provisions of CubeSmart's declaration of trust regarding restrictions on transfer of its shares.

Holders of CubeSmart's common shares have no preference, conversion, exchange, sinking fund, redemption or appraisal rights and have no preemptive rights to subscribe for any of our securities. Subject to the restrictions on transfer of shares contained in CubeSmart's declaration of trust and to the power of the board of trustees to create common shares with differing voting rights, all common shares have equal dividend, liquidation and other rights.

CubeSmart's declaration of trust provides that it may issue up to 40,000,000 preferred shares of beneficial interest, par value $0.01 per share. As of September 13, 2011, there were no preferred shares issued and outstanding.

CubeSmart's board of trustees is authorized to issue the preferred shares in one or more series and to fix and designate the rights, preferences, privileges and restrictions of the preferred shares, including:

The rights, preferences, privileges and restrictions of the preferred shares of each series will be fixed by articles supplementary relating to each series. We will describe the specific terms of a particular series of preferred shares in the prospectus supplement relating to that series, including:

The description of preferred shares above and the description of the terms of a particular series of preferred shares in the prospectus supplement are not complete. You should refer to the applicable articles supplementary for complete information.

CubeSmart's board of trustees could authorize, without shareholder approval, the issuance of preferred shares with terms and conditions that could have the effect of discouraging a takeover or other transaction in which holders of some or a majority of CubeSmart's shares might receive a premium for their shares over the then-prevailing market price of its shares. We currently do not expect that the board of trustees would require shareholder approval prior to such a preferred issuance. In addition, any preferred shares that CubeSmart issues would rank senior to its common shares with respect to the payment of distributions, in which case CubeSmart could not pay any distributions on its common shares until full distributions have been paid with respect to such preferred shares.

Power to Reclassify Shares and Issue Additional Common Shares or Preferred Shares

CubeSmart's declaration of trust authorizes its board of trustees to classify any authorized but unissued common and preferred shares and to reclassify any previously classified but unissued common shares and preferred shares of any series from time to time in one or more series, as authorized by the board of trustees. Prior to the issuance of shares of each class or series, the board of trustees is required by the Maryland REIT law and CubeSmart's declaration of trust to establish for each such class or series, subject to the provisions of CubeSmart's declaration of trust regarding the restrictions on transfer of shares of beneficial interest, the terms, preferences, conversion or other rights, voting powers, restrictions, limitations as to dividends or other distributions, qualifications and terms or conditions of redemption for each such class or series. As a result, CubeSmart's board of trustees could authorize the issuance of preferred shares that have priority over the common shares with respect to dividends, distributions and rights upon liquidation and with other terms and conditions that could have the effect of delaying, deterring or preventing a transaction or a change in control that might involve a premium price for holders of common shares or otherwise might be in their best interest.

To permit us increased flexibility in structuring possible future financings and acquisitions and in meeting other needs that might arise, CubeSmart's declaration of trust allows us to issue additional common shares or preferred shares and to classify or reclassify unissued common shares or preferred shares and thereafter to issue the classified or reclassified shares without shareholder approval, unless shareholder approval is required by applicable law or the rules of any stock exchange or automated quotation system on which CubeSmart's securities may be listed or traded. Although we have no present intention of doing so, we could issue a class or series of shares that could delay, deter or prevent a transaction or a change in control that might involve a premium price for holders of common shares or might otherwise be in their best interests.

Holders of CubeSmart's common shares do not have preemptive rights, which means they have no right to acquire any additional shares that we may issue at a subsequent date.

In order to qualify as a REIT under the Code, CubeSmart's shares must be beneficially owned by 100 or more persons during at least 335 days of a taxable year of 12 months or during a proportionate part of a shorter taxable year. Also, no more than 50% of the value of CubeSmart's outstanding shares (after taking into account options to acquire shares) may be owned, directly, indirectly or through attribution, by five or fewer individuals (as defined in the Code to include certain entities).

Because CubeSmart's board of trustees believes that it is in CubeSmart's shareholders' best interests to continue to qualify as a REIT and for anti-takeover and other strategic reasons, its declaration of trust, subject to certain exceptions, contains restrictions on the number of CubeSmart's shares of beneficial interest that a person may own. CubeSmart's declaration of trust provides that:

The excepted holder limit was established in light of the fact that Robert J. Amsdell, Barry L. Amsdell, Todd C. Amsdell and certain Amsdell Entities owned a substantial percentage of CubeSmart's common shares upon completion of its IPO. The excepted holder limit does not permit each excepted holder to own 29% of CubeSmart's common shares. Rather, the excepted holder limit prevents two or more excepted holders who are each treated as individuals under the applicable tax attribution rules from owning a higher percentage of CubeSmart's common shares than the maximum number of

common shares that could be owned by any one excepted holder (29%), plus the maximum number of common shares that could be owned by any one or more other individual common shareholders who are not excepted holders (5%). We do not believe the 29% expected holder limit for certain members of the Amsdell family and certain related entities will jeopardize CubeSmart's REIT status because no other individual shareholder can own more than 5% of the value of CubeSmart's outstanding common shares. Accordingly, no five individuals can own more than 49% of CubeSmart's shares and, thus, we will be in compliance with the REIT qualification requirement prohibiting five or fewer individuals from owning more than 50% of the value of CubeSmart's outstanding shares.

CubeSmart's board of trustees may waive the 5% ownership limit, or the 9.8% designated investment entity limit, for a shareholder that is not an individual if such shareholder provides information and makes representations to the board of trustees that are satisfactory to the board of trustees, in its reasonable discretion, to establish that such person's ownership in excess of the 5% limit or the 9.8% limit, as applicable, would not jeopardize CubeSmart's qualification as a REIT.

Any person who acquires or attempts or intends to acquire beneficial or constructive ownership of CubeSmart's shares that will or may violate any of the foregoing restrictions on transferability and ownership will be required to give notice immediately to us and provide us with such other information as we may request in order to determine the effect of such transfer on CubeSmart's status as a REIT. If any transfer of shares or any other event would otherwise result in any person violating the ownership limits described above, then CubeSmart's declaration of trust provides that (a) the transfer will be void and of no force or effect with respect to the prohibited transferee with respect to that number of shares that exceeds the ownership limits or that such number of shares will be automatically transferred to a charitable trust for the benefit of a charitable beneficiary and (b) the prohibited transferee would not acquire any right or interest in the shares. The foregoing restrictions on transferability and ownership will not apply if CubeSmart's board of trustees determines that it is no longer in CubeSmart's best interests to attempt to qualify, or to continue to qualify, as a REIT.

All certificates evidencing CubeSmart's shares bear a legend referring to the restrictions described above.

Every owner of more than 5% (or such lower percentage as required by the Code or the regulations promulgated thereunder) of all classes or series of CubeSmart's shares, including common shares, is required to give written notice to us within 30 days after the end of each taxable year stating the name and address of such owner, the number of shares of each class and series of shares that the owner beneficially owns and a description of the manner in which such shares are held. Each such owner shall provide to us such additional information as we may request in order to determine the

effect, if any, of such beneficial ownership on CubeSmart's status as a REIT and to ensure compliance with the ownership limitations. In addition, each shareholder shall upon demand be required to provide to us such information as we may request, in good faith, in order to determine CubeSmart's status as a REIT and to comply with the requirements of any taxing authority or governmental authority or to determine such compliance.

These ownership limitations could delay, deter or prevent a transaction or a change in control that might involve a premium price for the common shares or might otherwise be in the best interest of CubeSmart's shareholders.

The transfer agent and registrar for our common shares is American Stock Transfer & Trust Co., LLC. The transfer agent and registrar for our preferred shares will be set forth in the applicable prospectus supplement.

Certain Provisions of Maryland Law and CubeSmart's Declaration of Trust and Bylaws

The following description of certain provisions of Maryland law and of CubeSmart's declaration of trust and bylaws is only a summary. For a complete description, we refer you to the applicable Maryland law and CubeSmart declaration of trust and bylaws.

CubeSmart's declaration of trust and bylaws provide that the number of CubeSmart's trustees shall not be less than one and not more than 13, and will be established by a vote of a majority of the members of its board of trustees. Our bylaws provide that any vacancy, including a vacancy created by an increase in the number of trustees, may be filled only by a majority of the remaining trustees, even if the remaining trustees do not constitute a quorum. Pursuant to CubeSmart's declaration of trust, each of its trustees is elected by its shareholders to serve until the next annual meeting and until their successors are duly elected and qualify. Under Maryland law, CubeSmart's board of trustees may elect to create staggered terms for its members.

CubeSmart's bylaws provide that at least a majority of our trustees will be "independent," with independence being defined in the manner established by our board of trustees and in a manner consistent with listing standards established by the NYSE.

CubeSmart's declaration of trust provides that a trustee may be removed only with cause and only upon the affirmative vote of at least two-thirds of the votes entitled to be cast in the election of trustees. Absent removal of all of CubeSmart's trustees, this provision, when coupled with the provision in CubeSmart's bylaws authorizing CubeSmart's board of trustees to fill vacant trusteeships, may preclude shareholders from removing incumbent trustees and filling the vacancies created by such removal with their own nominees.

CubeSmart's board of trustees has approved a resolution that exempts CubeSmart from the provisions of the Maryland business combination statute described below, but its board of trustees may opt to make these provisions applicable to CubeSmart in the future. Maryland law prohibits "business combinations" between CubeSmart and an interested shareholder (defined below) or an affiliate of an interested shareholder for five years after the most recent date on which the interested shareholder becomes an interested shareholder. These business combinations include a merger, consolidation, share

exchange, or, in circumstances specified in the statute, an asset transfer or issuance or reclassification of equity securities. Maryland law defines an interested shareholder as:

A person is not an interested shareholder if CubeSmart's board of trustees approves in advance the transaction by which the person otherwise would have become an interested shareholder. However, in approving a transaction, CubeSmart's board of trustees may provide that its approval is subject to compliance, at or after the time of approval, with any terms and conditions determined by CubeSmart's board of trustees.

After the five-year prohibition, any business combination between CubeSmart and an interested shareholder generally must be recommended by CubeSmart's board of trustees and approved by the affirmative vote of at least:

These super-majority vote requirements do not apply if CubeSmart's common shareholders receive a minimum price, as described under Maryland law, for their shares in the form of cash or other consideration in the same form as previously paid by the interested shareholder for its shares.

The statute permits various exemptions from its provisions, including business combinations that are approved by CubeSmart's board of trustees before the time that the interested shareholder becomes an interested shareholder.

CubeSmart's bylaws contain a provision exempting any and all acquisitions of CubeSmart's shares from the provisions of the Maryland Control Share Acquisition Act. However, CubeSmart board of trustees may opt to make these provisions applicable to an acquisition of CubeSmart's shares at any time by amending or repealing this provision in the future, and may do so on a retroactive basis. Maryland law provides that "control shares" of a Maryland REIT acquired in a "control share acquisition" have no voting rights unless approved by a vote of two-thirds of the votes entitled to be cast on the matter. Shares beneficially owned by the acquiring person in a control share acquisition or by CubeSmart's officers or employees who are CubeSmart's trustees are excluded from the shares entitled to vote in accordance with the immediately preceding sentence. "Control shares" are shares that, if aggregated with all other shares previously acquired by the acquiring person, or in respect of which the acquiring person is able to exercise or direct the exercise of voting power (except solely by virtue of a revocable proxy), would entitle the acquiring person to exercise or direct the exercise of the voting power in electing trustees within one of the following ranges of voting power:

Control shares do not include shares the acquiring person is then entitled to vote as a result of having previously obtained shareholder approval. A "control share acquisition" means the acquisition of control shares, subject to certain exceptions.

A person who has made or proposes to make a control share acquisition may compel our board of trustees to call a special meeting of shareholders to be held within 50 days of demand to consider the voting rights of the shares. The right to compel the calling of a special meeting is subject to the satisfaction of certain conditions, including an undertaking to pay the expenses of the special meeting. If no request for a special meeting is made, we may present the question at any shareholders' meeting.

If voting rights are not approved at the shareholders' meeting or if the acquiring person does not deliver the statement required by Maryland law, then, subject to certain conditions and limitations, we may redeem any or all of the control shares, except those for which voting rights have previously been approved, for fair value. Fair value is determined without regard to the absence of voting rights for the control shares and as of the date of the last control share acquisition or of any meeting of shareholders at which the voting rights of the shares were considered and not approved. If voting rights for control shares are approved at a shareholders' meeting, the acquiror may then vote a majority of the shares entitled to vote, and all other shareholders may exercise appraisal rights. The fair value of the shares for purposes of these appraisal rights may not be less than the highest price per share paid by the acquiror in the control share acquisition. The control share acquisition statute does not apply to shares acquired in a merger, consolidation or share exchange if we are a party to the transaction, nor does it apply to acquisitions approved by or exempted by our declaration of trust or bylaws.

Possible Anti-Takeover Effect of Certain Provisions of Maryland Law and CubeSmart's Declaration of Trust and Bylaws

The business combination provisions of Maryland law (if CubeSmart's board of trustees opts to make them applicable to CubeSmart), the control share acquisition provisions of Maryland law (if the applicable provision in CubeSmart's bylaws is rescinded), the limitations on removal of trustees, the restrictions on the acquisition of CubeSmart's shares of beneficial interest, the power to issue additional common shares or preferred shares and the advance notice provisions for shareholder trustee nominations and other shareholder proposals of our bylaws could have the effect of delaying, deterring or preventing a transaction or a change in control that might involve a premium price for holders of the common shares or might otherwise be in their best interest. The "unsolicited takeovers" provisions of Maryland law permit our board of trustees, without shareholder approval and regardless of what is provided in our declaration of trust or bylaws, to implement takeover defenses that we may not yet have.

CubeSmart may elect to have shares of preferred shares represented by depositary shares. The shares of any series of the preferred shares underlying the depositary shares will be deposited under a separate deposit agreement between CubeSmart and a bank or trust company that we select. The prospectus supplement relating to a series of depositary shares will set forth the name and address of this preferred shares depositary. Subject to the terms of the deposit agreement, each owner of a depositary share will be entitled, proportionately, to all the rights, preferences and privileges of the preferred shares represented by such depositary share, including dividend, voting, redemption, conversion, exchange and liquidation rights. As of the date of this prospectus, there are no depositary shares outstanding.

The depositary shares will be evidenced by depositary receipts issued pursuant to the deposit agreement, each of which will represent the applicable interest in a number of shares of a particular series of the preferred shares described in the applicable prospectus supplement.

A holder of depositary shares will be entitled to receive the shares of preferred shares, but only in whole shares of preferred shares, underlying those depositary shares. If the depositary receipts delivered by the holder evidence a number of depositary shares in excess of the whole number of shares of preferred shares to be withdrawn, the depositary will deliver to that holder at the same time a new depositary receipt for the excess number of depositary shares.

The preferred shares depositary will distribute all cash dividends or other cash distributions in respect of the series of preferred shares represented by the depositary shares to the record holders of depositary receipts in proportion, to the extent possible, to the number of depositary shares owned by those holders. The depositary, however, will distribute only the amount that can be distributed without attributing to any depositary share a fraction of one cent, and any undistributed balance will be added to and treated as part of the next sum received by the depositary for distribution to record holders of depositary receipts then outstanding.

If there is a distribution other than in cash in respect of the preferred shares, the preferred shares depositary will distribute property received by it to the record holders of depositary receipts in proportion, insofar as possible, to the number of depositary shares owned by those holders, unless the preferred shares depositary determines that it is not feasible to make such a distribution. In that case, the preferred shares depositary may, with our approval, adopt any method that it deems equitable and practicable to effect the distribution, including a public or private sale of the property and distribution of the net proceeds from the sale to the holders.

The amount distributed in any of the above cases will be reduced by any amount we or the preferred shares depositary are required to withhold on account of taxes.

If any series of preferred shares underlying the depositary shares is subject to provisions relating to its conversion or exchange as set forth in an applicable prospectus supplement, each record holder of depositary receipts will have the right or obligation to convert or exchange the depositary shares evidenced by the depositary receipts pursuant to those provisions.

If any series of preferred shares underlying the depositary shares is subject to redemption, the depositary shares will be redeemed from the proceeds received by the preferred shares depositary resulting from the redemption, in whole or in part, of the preferred shares held by the preferred shares depositary. Whenever CubeSmart redeems a share of preferred shares held by the preferred shares depositary, the preferred shares depositary will redeem as of the same redemption date a proportionate number of depositary shares representing the shares of preferred shares that were redeemed. The redemption price per depositary share will be equal to the aggregate redemption price payable with respect to the number of shares of preferred shares underlying the depositary shares. If fewer than all the depositary shares are to be redeemed, the depositary shares to be redeemed will be selected by lot or proportionately as CubeSmart may determine.

After the date fixed for redemption, the depositary shares called for redemption will no longer be deemed to be outstanding and all rights of the holders of the depositary shares will cease, except the right to receive the redemption price. Any funds that we deposit with the preferred shares depositary relating to depositary shares which are not redeemed by the holders of the depositary shares will be returned to us after a period of two years from the date the funds are deposited by CubeSmart.

Upon receipt of notice of any meeting at which the holders of any shares of preferred shares underlying the depositary shares are entitled to vote, the preferred shares depositary will mail the information contained in the notice to the record holders of the depositary receipts. Each record holder of the depositary receipts on the record date, which will be the same date as the record date for the preferred shares, may then instruct the preferred shares depositary as to the exercise of the voting rights pertaining to the number of shares of preferred shares underlying that holder's depositary shares. The preferred shares depositary will try to vote the number of shares of preferred shares underlying the depositary shares in accordance with the instructions, and we will agree to take all reasonable action which the preferred shares depositary deems necessary to enable the preferred shares depositary to do so. The preferred shares depositary will abstain from voting the preferred shares to the extent that it does not receive specific written instructions from holders of depositary receipts representing the preferred shares.

Upon surrender of depositary receipts at the principal office of the preferred shares depositary, upon payment of any unpaid amount due the preferred shares depositary, and subject to the terms of the deposit agreement, the owner of the depositary shares evidenced by the depositary receipts is entitled to delivery of the number of whole shares of preferred shares and all money and other property, if any, represented by the depositary shares. Partial shares of preferred shares will not be issued. If the depositary receipts delivered by the holder evidence a number of depositary shares in excess of the number of depositary shares representing the number of whole shares of preferred shares to be withdrawn, the preferred shares depositary will deliver to the holder at the same time a new depositary receipt evidencing the excess number of depositary shares. Holders of preferred shares that are withdrawn will not be entitled to deposit the shares that have been withdrawn under the deposit agreement or to receive depositary receipts.

CubeSmart and the preferred shares depositary may at any time agree to amend the form of depositary receipt and any provision of the deposit agreement. However, any amendment that materially and adversely alters the rights of holders of depositary shares will not be effective unless the amendment has been approved by the holders of at least a majority of the depositary shares then outstanding. The deposit agreement may be terminated by CubeSmart or by the preferred shares depositary only if all outstanding shares have been redeemed or if a final distribution in respect of the underlying preferred shares has been made to the holders of the depositary shares in connection with our liquidation, dissolution or winding up.

CubeSmart will pay all charges of the preferred shares depositary including charges in connection with the initial deposit of the preferred shares, the initial issuance of the depositary receipts, the distribution of information to the holders of depositary receipts with respect to matters on which preference shares is entitled to vote, withdrawals of the preferred shares by the holders of depositary receipts or redemption or conversion of the preferred shares, except for taxes (including transfer taxes, if any) and other governmental charges and any other charges expressly provided in the deposit agreement to be at the expense of holders of depositary receipts or persons depositing preferred shares.

Neither CubeSmart nor the preferred shares depositary will be liable if either of us is prevented or delayed by law or any circumstance beyond our control in performing any obligations under the deposit agreement. The obligations of the preferred shares depositary under the deposit agreement are limited to performing its duties under the agreement without negligence or bad faith. Our obligations under the deposit agreement are limited to performing our duties in good faith. Neither CubeSmart nor the preferred shares depositary is obligated to prosecute or defend any legal proceeding in respect of any depositary shares or preferred shares unless satisfactory indemnity is furnished. CubeSmart and the preferred shares depositary may rely on advice of or information from counsel, accountants or other persons that they believe to be competent and on documents that they believe to be genuine.

The preferred shares depositary may resign at any time or be removed by CubeSmart, effective upon the acceptance by its successor of its appointment. If CubeSmart have not appointed a successor preferred shares depositary and the successor depositary has not accepted its appointment within 60 days after the preferred shares depositary delivered a resignation notice to CubeSmart, the preferred shares depositary may terminate the deposit agreement. See "—Amendment and Termination of the Deposit Agreement" above.

CubeSmart may issue subscription rights to purchase common shares, preferred shares, or depositary shares. CubeSmart may issue subscription rights independently or together with any other offered security, which may or may not be transferable by the shareholder. In connection with any offering of subscription rights, CubeSmart may enter into a standby arrangement with one or more underwriters or other purchasers pursuant to which the underwriters or other purchasers may be required to purchase any securities remaining unsubscribed for after such offering.

The prospectus supplement relating to any subscription rights CubeSmart may offer will contain the specific terms of the subscription rights. These terms may include the following:

The description in the applicable prospectus supplement of any subscription rights CubeSmart offers will not necessarily be complete and will be qualified in its entirety by reference to the applicable subscription rights certificate or subscription rights agreement, which will be filed with the SEC if CubeSmart offers subscription rights. For more information on how you can obtain copies of any subscription rights certificate or subscription rights agreement if CubeSmart offers subscription rights, see "Where You Can Find More Information." CubeSmart urges you to read the applicable subscription rights certificate, the applicable subscription rights agreement and any applicable prospectus supplement in their entirety.

CubeSmart may issue warrants for the purchase of common shares, preferred shares or depositary shares. CubeSmart may issue warrants independently or together with any offered securities. The warrants may be attached to or separate from those offered securities. CubeSmart will issue the warrants under one or more warrant agreements to be entered into between CubeSmart and a warrant agent to be named in the applicable prospectus supplement. The warrant agent will act solely as our agent in connection with the warrants and will not assume any obligation or relationship of agency or trust for or with any holders or beneficial owners of warrants.

The prospectus supplement relating to any warrants that CubeSmart may offer will contain the specific terms of the warrants. These terms may include the following:

Each warrant will entitle the holder of the warrant to purchase for cash the amount of CubeSmart's common shares, preferred shares and/or depositary shares, as the case may be, at the exercise price stated or determinable in the applicable prospectus supplement for the warrants. Warrants may be exercised at any time up to the close of business on the expiration date shown in the applicable prospectus supplement, unless otherwise specified in such prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void. Warrants may be exercised as described in the applicable prospectus supplement. When the warrant holder makes the payment and properly completes and signs the warrant certificate at the corporate trust office of the warrant agent or any other office indicated in the prospectus supplement, CubeSmart will, as soon as possible, forward the common shares, preferred shares and/or depositary shares that the warrant holder has purchased, as the case may be. If the warrant holder exercises the warrant for less than all of the

warrants represented by the warrant certificate, CubeSmart will issue a new warrant certificate for the remaining warrants.

The description in the applicable prospectus supplement of any warrants CubeSmart offers will not necessarily be complete and will be qualified in its entirety by reference to the applicable warrant agreement and warrant certificate, which will be filed with the SEC if CubeSmart offers warrants. For more information on how you can obtain copies of any warrant certificate or warrant agreement if we offer warrants, see "Where You Can Find More Information." We urge you to read the applicable warrant certificate, the applicable warrant agreement and any applicable prospectus supplement in their entirety.

The following summary sets forth the general terms and provisions of the indenture under which the debt securities will be issued by the Operating Partnership. The debt securities will be issued by the Operating Partnership under an indenture, as amended or supplemented from time to time, among the Operating Partnership, CubeSmart, as guarantor, and U.S. Bank National Association, as trustee.

The debt securities may be issued from time to time in one or more series. The particular terms and provisions of the debt securities with respect to a specific offering of debt securities will be set forth in the applicable prospectus supplement. This summary of general terms and provisions of the indenture and the debt securities does not purport to be complete and is subject to, and is qualified in its entirety by reference to, all provisions of the indenture and those debt securities.

The indenture is filed as an exhibit to the registration statement of which this prospectus is a part and will be available for inspection at the corporate trust office of the trustee or as described under "Where You Can Find More Information." The indenture will be qualified under, subject to, and governed by, the Trust Indenture Act of 1939, as amended, or the Trust Indenture Act.

All section references appearing herein are to sections of the indenture, and capitalized terms used but not defined herein will have the respective meanings set forth in the indenture.

The debt securities will be direct, unsecured obligations of the Operating Partnership. Except for any series of debt securities which is expressly subordinated to other indebtedness of the Operating Partnership, the debt securities will rank equally with all other unsecured and unsubordinated indebtedness of the Operating Partnership. Under the indenture, the debt securities may be issued without limit as to aggregate principal amount, in one or more series, as established from time to time pursuant to authority granted by a resolution of the board of trustees of CubeSmart as sole general partner of the Operating Partnership or as established in one or more supplemental indentures to the indenture. All of the debt securities of any one series need not be issued at the same time and, unless otherwise provided, a series may be reopened, without the consent of the holders of the debt securities of that series, for issuances of additional debt securities of that series. All debt securities of a particular series shall be substantially identical except as to denomination, date of issuance, issue price and the date from which interest, if any, shall accrue.

All of the debt securities will be fully and unconditionally guaranteed as to payment of principal and premium, if any, and interest by CubeSmart. The indenture allows certain of our subsidiaries from time to time to become guarantors of specific series of the debt securities.

The indenture provides that there may be more than one trustee for any one or more series of debt securities. Any trustee under the indenture may resign or be removed with respect to one or more series of debt securities, and a successor trustee may be appointed to act with respect to that series. Except as otherwise indicated in this prospectus or the applicable prospectus supplement, any action to be taken by the trustee may be taken by each such trustee with respect to, and only with respect to, the one or more series of debt securities for which it is trustee under the indenture.

The applicable prospectus supplement relating to the series of debt securities being offered will describe the specific terms and provisions of those debt securities, including the following:

The debt securities may provide for less than the entire principal amount of those debt securities to be payable upon declaration of acceleration of the maturity thereof ("original issue discount securities"). The applicable prospectus supplement will describe special U.S. federal income tax, accounting and other considerations applicable to the original issue discount securities.

The indenture does not contain any provisions that would limit the ability of the Operating Partnership to incur indebtedness or that would afford holders of debt securities protection in the event of a highly leveraged or similar transaction involving the Operating Partnership. However, restrictions on ownership and transfers of CubeSmart's common shares and preferred shares, designed to preserve CubeSmart's status as a REIT, may prevent or hinder a change of control. Reference is made to the applicable prospectus supplement for information with respect to any deletions from, modifications of or additions to the events of default or covenants of the Operating Partnership that are described below, including any addition of a covenant or other provision providing event risk or similar protection.

CubeSmart will, under the indenture, fully and unconditionally guarantee the due and punctual payment of principal of and premium, if any, and interest on all debt securities issued by the Operating Partnership, and the due and punctual payment of any sinking fund payments on those debt securities, when and as the same will become due and payable, whether at a maturity date, by declaration of acceleration, call for redemption or otherwise.

From time to time, subsidiaries of the Operating Partnership may join as guarantors under the indenture. Such subsidiaries' guarantees will be limited to the series of debt securities for which they execute notations of guarantee in accordance with the terms of the indenture, and may be released in connection with:

The obligations of each guarantor, other than CubeSmart, under its guarantee will be limited as necessary to prevent that guarantee from constituting a fraudulent conveyance or fraudulent transfer under applicable law.

Unless otherwise specified in the applicable prospectus supplement, the debt securities of any series shall be issuable only in registered form without coupons and, other than securities in global form (which may be of any denomination), will be issuable in denominations of $2,000 and integral multiples of $1,000 in excess thereof.

Unless otherwise specified in the applicable prospectus supplement, the principal of and premium, if any, and interest on any series of debt securities will be payable at the corporate trust office of the trustee. However, at the option of the Operating Partnership, payment of interest may be made by check mailed to the address of the person entitled thereto as it appears in the security register or by wire transfer of funds to that person at a bank account maintained within the United States.

All amounts paid by the Operating Partnership to a paying agent or a trustee for the payment of the principal of or premium, if any, or interest on any debt security which remain unclaimed at the end of two years after the principal, premium or interest has become due and payable will be repaid to the Operating Partnership, and the holder of the debt security thereafter may look only to the Operating Partnership for payment of these amounts.

Any interest not punctually paid or duly provided for on any interest payment date with respect to a debt security will forthwith cease to be payable to the holder on the applicable regular record date and may either be paid to the person in whose name that debt security is registered at the close of business on a special record date for the payment of that defaulted interest to be fixed by the trustee or may be paid at any time in any other lawful manner, all in accordance with the indenture. Notice of any special record date will be given to the holder of that debt security not less than 10 days prior to the special record date.

Subject to certain limitations imposed upon debt securities issued in book-entry form, the debt securities of any series will be exchangeable for other debt securities of the same series, of a like aggregate principal amount and tenor, of different authorized denominations upon surrender of such debt securities at the corporate trust office of the trustee. In addition, subject to certain limitations imposed upon debt securities issued in book-entry form, the debt securities of any series may be surrendered for registration of transfer at the corporate trust office of the trustee.

Every debt security surrendered for registration of transfer or exchange will be duly endorsed or accompanied by a written instrument of transfer. No service charge will be made for any registration of transfer or exchange of any debt securities, but the Operating Partnership may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

If the applicable prospectus supplement refers to any transfer agent (in addition to the trustee) initially designated by the Operating Partnership and the guarantors with respect to any series of debt securities, the Operating Partnership may at any time rescind the designation of that transfer agent or approve a change in the location through which that transfer agent acts, except that the Operating Partnership and the guarantors will be required to maintain a transfer agent in each place of payment for that series. The Operating Partnership and the guarantors may at any time designate additional transfer agents with respect to any series of debt securities.

Unless otherwise provided in the applicable prospectus supplement, the Operating Partnership may consolidate with, or sell, lease or convey all or substantially all of its assets to, or merge with or into, any other entity, provided that the following conditions are satisfied or fulfilled:

Unless otherwise provided in the applicable prospectus supplement, CubeSmart may consolidate with, or sell, lease or convey all or substantially all its assets to, or merge with or into, any other entity, provided that substantially the same conditions as above are satisfied or fulfilled.

We will set forth in the applicable prospectus supplement any financial covenants applicable to any issue of debt securities.

Unless otherwise provided in the applicable prospectus supplement, so long as any debt securities are outstanding, CubeSmart and the Operating Partnership will furnish to the trustee such information, documents and other reports as may be required by the Trust Indenture Act, including filing with the trustee within 15 days information, documents or reports required to be filed by the Issuer with the SEC.

The Operating Partnership and the guarantors may choose not to comply with any term, provision or condition of certain covenants if at any time the holders of at least a majority in principal amount of all the outstanding debt securities, by act of those holders, either waive compliance in that instance or generally waive compliance with that covenant. Except to the extent so expressly waived, and until any waiver becomes effective, the Operating Partnership's and the guarantors' obligations and the duties of the trustee in respect of any such term, provision or condition will remain in full force and effect.

Unless otherwise provided in the applicable prospectus supplement, except as permitted under "Merger, Consolidation or Sale," each of the Operating Partnership and the guarantors will do or cause to be done all things necessary to preserve and keep in full force and effect its existence, rights (declaration and statutory) and franchises; provided, however, that neither the Operating Partnership nor any guarantor will be required to preserve any right or franchise if the board of directors of the Operating Partnership, or the board of trustees or analogous body of any subsidiary guarantor, determines that the preservation thereof is no longer necessary or desirable in the conduct of its business and that the loss of that right or franchise is not disadvantageous in any material respect to the holders of the debt securities.

Unless otherwise provided in the applicable prospectus supplement, each of the Operating Partnership and the guarantors will cause all of its material properties used or useful in the conduct of its business or the business of any of its Subsidiaries to be maintained and kept in good condition, repair and working order, all as in the judgment of the Operating Partnership or the applicable guarantor may be necessary so that the business carried on in connection with those properties may be properly and advantageously conducted at all times; provided, however, that, subject to the covenant described under "Merger, Consolidation and Sale" above, neither the Operating Partnership nor any guarantor nor any of their respective Subsidiaries will be prevented from selling or otherwise disposing of their properties at any time.

Unless otherwise provided in the applicable prospectus supplement, each of the Operating Partnership and the guarantors will pay or discharge or cause to be paid or discharged, before becoming delinquent:

provided, however, that neither the Operating Partnership nor any guarantor will be required to pay or discharge or cause to be paid or discharged any tax, assessment, charge or claim whose amount or applicability is being contested in good faith.

Unless otherwise provided in the applicable prospectus supplement, each of the Operating Partnership and the guarantors will pay to any holder of debt securities that is a United States Alien such additional amounts as may be required such that every net payment on the debt securities held by such holder, after deduction or withholding on account of any present or future U.S. tax (other than taxes unrelated to the holder's ownership of the debt securities and certain other taxes), is not less than the amount provided in such debt securities as then due and payable.

The applicable prospectus supplement relating to the series of debt securities being offered will describe any additional covenants specific to that series.

Unless otherwise provided in the applicable prospectus supplement, the indenture provides that the following events will be "events of default" with respect to any series of debt securities issued under the indenture:

Unless otherwise provided in the applicable prospectus supplement, if an event of default (other than as described in clause (6) above) with respect to debt securities of any series at the time outstanding occurs and is continuing, then in each case the trustee or the holders of not less than 25% in principal amount of the outstanding debt securities of that series may declare the principal (or, if the debt securities of that series are original issue discount securities or indexed securities, that portion of the principal amount as may be specified in the terms thereof) of and premium, if any, and accrued and unpaid interest on all of the debt securities of that series to be due and payable immediately by written notice thereof to the Operating Partnership and CubeSmart (and to the trustee if given by the holders). If an event of default described in clause (6) above occurs and is continuing, the principal (or such portion thereof) of and premium, if any, and accrued and unpaid interest on all of the debt securities of that series will become and be immediately due and payable without any declaration or other act on the part of the trustee or any holders. However, at any time after any acceleration with respect to debt securities of that series, but before a judgment or decree for payment of the amounts due has been obtained by the trustee, the holders of not less then a majority in principal amount of outstanding debt securities of that series may rescind and annul that acceleration and its consequences if (1) the Operating Partnership or any guarantor has paid or deposited with the trustee all required payments of the principal of and premium, if any, and interest on the debt securities of that series

(without giving effect to the acceleration) plus certain fees, expenses, disbursements and, premium, if any, advances of the trustee and (2) all events of default, other than the nonpayment of accelerated principal, premium, if any, or interest with respect to debt securities of that series, have been cured or waived as provided in the indenture. The indenture also provides that the holders of not less than a majority in principal amount of the outstanding debt securities of any series may waive any past default with respect to that series and its consequences, except a default (A) in the payment of the principal of or premium, if any, or interest on any debt security of that series or (B) in respect of a covenant or provision contained in the indenture that cannot be modified or amended without the consent of the holder of each outstanding debt security affected thereby.

The trustee will be required to give notice to the holders of debt securities within 90 days of a default under the indenture unless such default has been cured or waived; provided, however, that the trustee may withhold notice to the holders of any series of debt securities of any default with respect to that series (except a default in the payment of the principal of or premium, if any, or interest on any debt securities of that series or in the payment of any sinking fund installment in respect of any debt securities of that series) if the responsible officers of the trustee consider withholding of notice to be in the interest of the holders.

The indenture provides that no holders of debt securities of any series may institute any judicial or other proceedings with respect to the indenture or for any remedy thereunder, except in the case of failure of the trustee, for 60 days, to act after it has received a written request to institute proceedings in respect of an event of default from the holders of not less than 25% in principal amount of the outstanding debt securities of that series, as well as an offer of reasonable security or indemnity. This provision will not prevent, however, any holder of debt securities from instituting suit for the enforcement of payment of the principal of and premium, if any, and interest on the debt securities at the respective due date or dates for payment.

Subject to provisions in the indenture relating to its duties in case of default, the trustee is under no obligation to exercise any of its rights or powers under the indenture at the request or direction of any holders of debt securities of any series then outstanding under the indenture, unless the holders offer to the trustee reasonable security or indemnity. The holders of not less than a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or of exercising any trust or power conferred upon the trustee for that series. However, the trustee may refuse to follow any direction which is in conflict with any law or the indenture, which may involve the trustee in personal liability or which may be unduly prejudicial to the holders of debt securities of that series not joining in the proceeding.

Within 120 days after the end of each fiscal year, the Operating Partnership and CubeSmart must deliver to the trustee a certificate, signed by one of several specified officers of the general partner of the Operating Partnership and of CubeSmart, stating whether or not such officers have knowledge of any default under the indenture and, if so, specifying each such default and the nature and status thereof.

Modifications and amendments of provisions of the indenture applicable to any series may be made only with consent of the holders of more than 50% in principal amount of all outstanding debt securities which are affected by the modification or amendment; provided, however, that no such modification or amendment may, without the consent of the holder of each debt security affected thereby:

Modifications and amendments of the indenture may be made by the Operating Partnership, the guarantors and the trustee without the consent of any holder of debt securities for any of the following purposes:

The indenture provides that, in determining whether the holders of the requisite principal amount of outstanding debt securities of a series have given any request, demand, authorization, direction, notice, consent or waiver thereunder or whether a quorum is present at a meeting of holders of debt securities:

The indenture contains provisions for convening meetings of the holders of debt securities of a series. A meeting may be called at any time by the trustee, and also, upon request, by the Operating Partnership or the holders of at least 25% in principal amount of the outstanding debt securities of that series, in each case upon notice given as provided in the indenture. Except for any consent that must be given by the holder of each debt security affected by certain modifications and amendments of the indenture, any resolution presented at a meeting or adjourned meeting duly reconvened at which a quorum is present may be adopted by the affirmative vote of the holders of a majority in principal amount of the outstanding debt securities of that series; provided, however, that, except as referred to above, any resolution with respect to any request, demand, authorization, direction, notice, consent, waiver or other action that may be made, given or taken by the holders of a specified percentage, which is less than a majority, in principal amount of the outstanding debt securities of a series may be adopted at a meeting or adjourned meeting duly reconvened at which a quorum is present by the affirmative vote of the holders of the debt securities of that series. Any resolution passed or decision taken at any meeting of holders of debt securities of any series duly held in accordance with the indenture will be binding on all holders of debt securities of that series. The quorum at any meeting called to adopt a resolution, and at any reconvened meeting, will be persons holding or representing a majority in principal amount of the outstanding debt securities of a series; provided, however, that if any action is to be taken at such meeting with respect to a consent or waiver which may be given by the holders of not less than a specified percentage in principal amount of the outstanding debt securities of a series, the persons holding or representing such specified percentage in principal amount of the outstanding debt securities of such series will constitute a quorum.

Notwithstanding the foregoing provisions, if any action is to be taken at a meeting of holders of debt securities of any series with respect to any request, demand, authorization, direction, notice, consent, waiver or other action that the indenture expressly provides may be made, given or taken by the holders of a specified percentage in principal amount of all outstanding debt securities affected thereby, or of the holders of that series and one or more additional series:

Unless otherwise provided in the applicable prospectus supplement, the Operating Partnership and the guarantors may discharge certain obligations to holders of any series of debt securities that have not already been delivered to the trustee for cancellation and that either have become due and payable or will become due and payable within one year (or are scheduled for redemption within one year) by irrevocably depositing with the trustee, in trust, funds in such currency or currencies, currency unit or units or composite currency or currencies in which such debt securities are payable in an amount sufficient to pay the entire indebtedness on such debt securities in respect of principal and premium, if any, and interest to the date of such deposit (if such debt securities have become due and payable) or to the stated maturity or redemption date, as the case may be.

In addition, the indenture provides that, unless otherwise provided in the applicable prospectus supplement, the Operating Partnership may elect either:

in either case upon the irrevocable deposit by the Operating Partnership or the guarantors with the trustee, in trust, of any amount, in such currency or currencies, currency unit or units or composite currency or currencies in which those debt securities are payable at stated maturity, or Government Obligations, or both, applicable to those debt securities which through the scheduled payment of principal and interest in accordance with their terms will provide money in an amount sufficient, based on a certification by officers of the Operating Partnership, to pay the principal of and premium, if any, and interest on such debt securities, and any mandatory sinking fund or analogous payments thereon, on the scheduled due dates.

This trust may only be established if, among other conditions, the Operating Partnership has delivered to the trustee an opinion of counsel to the effect that the holders of the debt securities will not recognize income, gain or loss for U.S. federal income tax purposes as a result of legal defeasance or covenant defeasance, as the case may be, and will be subject to U.S. federal income tax on the same amounts, in the same manner and at the same times as would have been the case if legal defeasance or covenant defeasance, as the case may be, had not occurred, and the opinion of counsel, in the case of legal defeasance, must refer to and be based upon a ruling of the Internal Revenue Service or a change in applicable U.S. federal income tax law occurring after the date of the indenture.

In the event the Operating Partnership effects covenant defeasance with respect to the debt securities of any series and those debt securities are declared due and payable because of the occurrence of any event of default other than an event of default described in clause (4) under "Events of Default, Notice and Waiver" with respect to the covenants described under "—Covenants" (which would no longer be applicable to those debt securities) or described in clause (7) under "Events of Default, Notice and Waiver" with respect to any other covenant as to which there has been covenant defeasance, the amount in the currency, currency unit or composite currency in which those debt securities are payable, and Government Obligations on deposit with the trustee, will be sufficient to pay amounts due on those debt securities at the time of their stated maturity but may not be sufficient to pay amounts due on those debt securities at the time of the acceleration resulting from such event of default. However, the Operating Partnership and the guarantors would remain liable to make payment of those amounts due at the time of acceleration.

The applicable prospectus supplement may further describe the provisions, if any, permitting legal defeasance or covenant defeasance, including any modifications to the provisions described above, with respect to the debt securities of a particular series.

The terms and conditions, if any, upon which the debt securities of any series will be subordinated to other indebtedness of the Operating Partnership, including the debt securities of other series, will be set forth in the applicable prospectus supplement. These terms will include a description of the indebtedness ranking senior to the debt securities of that series, the restrictions on payments to the holders of the debt securities of that series while a default with respect to the senior indebtedness is continuing, the restrictions, if any, on payments to the holders of the debt securities of that series following an event of default, and provisions requiring holders of the debt securities of that series to remit certain payments to holders of senior indebtedness.

The debt securities of a series may be issued in whole or in part in the form of one or more securities in global form that will be deposited with, or on behalf of, a depository identified in the applicable prospectus supplement relating to that series. Global securities, if any, issued in the United States are expected to be deposited with The Depository Trust Company, or "DTC," as depository. Unless otherwise indicated, global securities will be issued in fully registered form and in either temporary or permanent form. Unless the applicable prospectus supplement states otherwise, and until it is exchanged in whole or in part for the debt securities represented thereby, a global security may not be transferred except as a whole by the depository for that global security to a nominee of that depository or by a nominee of that depository to that depository or another nominee of such depository or by that depository or any nominee of that depository to a successor depository or any nominee of that successor.

The specific terms of the depository arrangement with respect to a series of debt securities will be described in the applicable prospectus supplement. We anticipate that, unless otherwise indicated in the applicable prospectus supplement, the following provisions will apply to depository arrangements.

The applicable prospectus supplement will state whether the global securities will be issued in certificated or book-entry form. If the global securities are to be issued in book-entry form, we expect that upon the issuance of a global security, the depository for the global security or its nominee will credit on its book-entry registration and transfer system the respective principal amounts of the individual debt securities represented by the global security to the accounts of persons that have accounts with such depository ("participants"). These accounts will be designated by the underwriters, dealers or agents with respect to the debt securities. Ownership of beneficial interests in a global security will be limited to participants or persons that may hold interests through participants.

We expect that, for the global securities deposited with DTC, pursuant to procedures established by DTC, ownership of beneficial interests in any global security with respect to which DTC is the depository will be shown on, and the transfer of that ownership will be effected only through, records maintained by DTC or its nominee (with respect to beneficial interests of participants) and records of participants (with respect to beneficial interests of persons who hold through participants). None of the Operating Partnership, the guarantors, the trustee, any paying agent and the security registrar will have any responsibility or liability for any aspect of the records of DTC or for maintaining, supervising or reviewing any records of DTC or any of its participants relating to beneficial ownership interests in the debt securities. The laws of some states require that certain purchasers of securities take physical delivery of such securities in definitive form. These limits and laws may impair the ability to own, pledge or transfer beneficial interest in a global security.

Unless otherwise specified in the applicable prospectus supplement or the actual global security, so long as the depository for a global security or its nominee is the registered owner of the book-entry global security, the depository or that nominee, as the case may be, will be considered the sole owner or holder of the debt securities represented by that global security for all purposes under the applicable indenture. Except as described below or in the applicable prospectus supplement or the global security, owners of beneficial interest in a global security will not be entitled to have any of the individual debt securities represented by the global security registered in their names, will not receive or be entitled to receive delivery of debt securities in definitive certificated form and will not be considered the owners or holders thereof under the applicable indenture. Beneficial owners of debt securities evidenced by a global security will not be considered the owners or holders thereof under the indenture for any purpose, including with respect to the giving of any direction, instructions or approvals to the trustee thereunder. Accordingly, each person owning a beneficial interest in a global security with respect to which DTC is the depository must rely on the procedures of DTC and, if that person is not a participant, on the procedures of the participant through which that person owns its interests, to

exercise any rights of a holder under the applicable indenture. We understand that, under existing industry practice, if we request any action of holders or if an owner of a beneficial interest in a global security desires to give or take any action which a holder is entitled to give or take under the applicable indenture, DTC would authorize the participants holding the relevant beneficial interest to give or take that action, and the participants would authorize beneficial owners through the participants to give or take that action or would otherwise act upon the instructions of beneficial owners holding through them.

Payments of principal of and premium, if any, and interest on debt securities represented by a global security registered in the name of a depository or its nominee will be made to or at the direction of the depository or its nominee, as the case may be, as the registered owner of the global security under the indenture. Under the terms of the indenture, the Operating Partnership, the guarantors, the trustee, any paying agent and the security registrar may treat the persons in whose name debt securities, including a global security, are registered as the owners thereof for the purpose of receiving such payments. Consequently, none of the Operating Partnership, the guarantors, the trustee, any paying agent and the security registrar has or will have any responsibility or liability for the payment of those amounts to beneficial owners of debt securities (including principal, premium, if any, and interest). We believe, however, that it is currently the policy of DTC to immediately credit the accounts of relevant participants with payments, in amounts proportionate to their respective holdings of beneficial interests in the relevant global security as shown on the records of DTC or its nominee. Payments by participants to owners of beneficial interests in the global security held through participants will be governed by standing instructions and customary practices, as is the case with securities held for the account of customers in bearer form or registered in street name, and will be the responsibility of the participants. Redemption notices with respect to any debt securities represented by a global security will be sent to the depository or its nominee. If less than all of the debt securities of any series are to be redeemed, we expect the depository to determine the amount of the interest of each participant in the debt securities to be redeemed to be determined by lot. None of the Operating Partnership, the guarantors, the trustee, any paying agent and the security registrar for the debt securities will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in the global security for the debt securities or for maintaining any records with respect thereto.

None of the Operating Partnership, the guarantors, the trustee, any paying agent and the security registrar will be liable for any delay by the holders of a global security or the depository in identifying the beneficial owners of debt securities and the Operating Partnership, the guarantors and the trustee may conclusively rely on, and will be protected in relying on, instructions from the holder of a global security or the depository for all purposes. The rules applicable to DTC and its participants are on file with the SEC.

If a depository for any debt securities is at any time unwilling, unable or ineligible to continue as depository and a successor depository is not appointed by the Operating Partnership within 90 days, the Operating Partnership will issue definitive certificated debt securities in exchange for the global security representing those debt securities. If an event of default has occurred and is continuing with respect to the debt securities of any series, the Operating Partnership will issue definitive certificated debt securities in exchange for the global security or securities representing the debt securities of such series. In addition, the Operating Partnership may at any time and in its sole discretion, subject to any limitations described in the applicable prospectus supplement or the global security relating to the debt securities, determine not to have any of the debt securities represented by one or more global securities and in such event will issue definitive certificated debt securities in exchange for the global security or securities representing the debt securities.

The debt securities of a series may also be issued in whole or in part in the form of one or more bearer global securities that will be deposited outside of the United States with a depository, or with a

nominee for the depository, identified in the applicable prospectus supplement and/or global security. Any such bearer global securities may be issued in temporary or permanent form. The specific terms and procedures, including the specific terms of the depository arrangement, with respect to any portion of a series of debt securities to be represented by one or more bearer global securities will be described in the applicable prospectus supplement and/or global security.

The following are certain defined terms used in this prospectus and the indenture. We refer you to the indenture for the complete definition of all defined terms, as well as any other capitalized terms used in this prospectus or the applicable prospectus supplement for which no definition is provided (Section 101).

For purposes of the following definitions and the indenture generally, all calculations and determinations will be made in accordance with generally accepted accounting principles and will be based upon the consolidated financial statements of the Operating Partnership and its Subsidiaries prepared in accordance with generally accepted accounting principles.

"Subsidiary" means, as to any person, (a) any corporation more than 50% of whose stock of any class or classes having by the terms thereof ordinary voting power to elect a majority of the directors of such corporation (irrespective of whether or not at the time, any class or classes of stock of such corporation shall have or might have voting power by reason of the lapse of time or the happening of any contingency) is at the time owned by such person directly or indirectly through Subsidiaries, and (b) any partnership, association, joint venture, limited liability company, trust or other entity in which such person directly or indirectly through Subsidiaries has more than a 50% equity interest or 50% Capital Percentage at any time. For the purpose of this definition, "Capital Percentage" means, with respect to the interest of CubeSmart, the Operating Partnership or one of its Subsidiaries in any partnership, association, joint venture, limited liability company, trust or other entity, the percentage interest of such partnership, association, joint venture, limited liability company, trust or other entity based on the aggregate amount of net capital contributed by CubeSmart, the Operating Partnership or such Subsidiary in such partnership, association, joint venture, limited liability company, trust or other entity at the time of determination relative to all capital contributions made in such partnership, association, joint venture, limited liability company, trust or other entity at such time of determination.

"United States Alien" means any corporation, partnership, individual or fiduciary that is, as to the United States, a foreign corporation, a nonresident alien individual, a nonresident fiduciary of a foreign estate or trust, or a foreign partnership one or more of the members of which is, as to the United States, a foreign corporation, a nonresident alien individual or a nonresident fiduciary of a foreign estate or trust.

This section summarizes the current material federal income tax considerations relating to the purchase, ownership and disposition of common shares of CubeSmart and debt securities of the Operating Partnership, and the qualification and taxation of CubeSmart as a REIT.

If CubeSmart offers one or more series of preferred shares under this prospectus, information about any income tax consequences to holders of those preferred shares will be included in an applicable prospectus supplement.

This discussion is not exhaustive of all possible tax considerations and does not provide a detailed discussion of any state, local or foreign tax considerations. The discussion does not address all aspects of taxation that may be relevant to particular investors in light of their personal investment or tax circumstances, or to certain types of investors that are subject to special treatment under the federal income tax laws, such as insurance companies, regulated investment companies, REITs, tax-exempt organizations (except to the limited extent discussed below under "Taxation of Tax-Exempt Shareholders"), financial institutions or broker-dealers, non-U.S. individuals and foreign corporations (except to the limited extent discussed below under "Taxation of Non-U.S. Shareholders") and other persons subject to special tax rules. This summary deals only with investors who hold common shares of CubeSmart or debt securities of the Operating Partnership as "capital assets" within the meaning of Section 1221 of the of the Internal Revenue Code of 1986, as amended (the "Code"). This discussion is not intended to be, and should not be construed as, tax advice.

The information in this summary is based on the Code, current, temporary and proposed Treasury regulations, the legislative history of the Code, current administrative interpretations and practices of the Internal Revenue Service, including its practices and policies as endorsed in private letter rulings, which are not binding on the Internal Revenue Service, and existing court decisions. Future legislation, regulations, administrative interpretations and court decisions could change current law or adversely affect existing interpretations of current law. Any change could apply retroactively. We have not obtained any rulings from the Internal Revenue Service concerning the tax treatment of the matters discussed in this summary. Therefore, it is possible that the Internal Revenue Service could challenge the statements in this summary, which do not bind the Internal Revenue Service or the courts, and that a court could agree with the Internal Revenue Service.

We urge you to consult your own tax advisor regarding the specific tax consequences to you of ownership of common shares of CubeSmart and debt securities of the Operating Partnership, and of CubeSmart's election to be taxed as a REIT. Specifically, you should consult your own tax advisor regarding the federal, state, local, foreign, and other tax consequences of such ownership and election, and regarding potential changes in applicable tax laws.

CubeSmart elected to be taxed as a REIT under the federal income tax laws beginning with its short taxable year ended December 31, 2004. CubeSmart believes that, beginning with such short taxable year, it has been organized and has operated in such a manner as to qualify for taxation as a REIT under the Code and intends to continue to operate in such a manner. However, there can be no assurance that CubeSmart has qualified or will remain qualified as a REIT.

CubeSmart's continued qualification and taxation as a REIT depend upon its ability to meet on a continuing basis, through actual annual operating results, certain qualification tests set forth in the federal income tax laws. Those qualification tests involve the percentage of income that CubeSmart earns from specified sources, the percentage of its assets that falls within specified categories, the diversity of its share ownership, and the percentage of its earnings that CubeSmart distributes.

Accordingly, no assurance can be given that the actual results of CubeSmart's operations for any particular taxable year will satisfy such requirements. For a discussion of the tax consequences of its failure to qualify as a REIT, see "Requirements for Qualification—Failure to Qualify" below.

Pursuant to CubeSmart's declaration of trust, CubeSmart's board of trustees has the authority to make any tax elections on its behalf that, in its sole judgment, are in CubeSmart's best interest. This authority includes the ability to revoke or otherwise terminate CubeSmart's status as a REIT. CubeSmart's board of trustees has the authority under its declaration of trust to make these elections without the necessity of obtaining the approval of CubeSmart's shareholders. In addition, CubeSmart's board of trustees has the authority to waive any restrictions and limitations contained in its declaration of trust that are intended to preserve CubeSmart's status as a REIT during any period in which its board of trustees has determined not to pursue or preserve CubeSmart's status as a REIT.

The sections of the Code relating to qualification and operation as a REIT, and the federal income taxation of a REIT, are highly technical and complex. The following discussion sets forth only the material aspects of those sections. This summary is qualified in its entirety by the applicable Code provisions and the related rules and regulations.

If CubeSmart qualifies as a REIT, it generally will not be subject to federal income tax on the taxable income that it distributes to its shareholders. The benefit of that tax treatment is that it avoids the "double taxation," or taxation at both the corporate and shareholder levels, that generally results from owning shares in a corporation. However, CubeSmart will be subject to federal tax in the following circumstances:

In addition, we may be subject to a variety of taxes, including payroll taxes and state, local and foreign income, property and other taxes on our assets and operations. We could also be subject to tax in situations and on transactions not presently contemplated.

To qualify as a REIT, CubeSmart must elect to be treated as a REIT, and CubeSmart must meet various (a) organizational requirements, (b) gross income tests, (c) asset tests, and (d) annual distribution requirements.

Organizational Requirements. A REIT is a corporation, trust or association that meets each of the following requirements:

CubeSmart must meet requirements 1 through 4, 8 and 9 during its entire taxable year and must meet requirement 5 during at least 335 days of a taxable year of 12 months, or during a proportionate part of a taxable year of less than 12 months. If CubeSmart complies with all the requirements for ascertaining information concerning the ownership of its outstanding shares in a taxable year and has no reason to know that it violated requirement 6, CubeSmart will be deemed to have satisfied requirement 6 for that taxable year. CubeSmart's declaration of trust provides for restrictions regarding the ownership and transfer of its shares of beneficial interest that are intended to assist CubeSmart in continuing to satisfy requirements 5 and 6. However, these restrictions may not ensure that CubeSmart will, in all cases, be able to satisfy these requirements. The provisions of the declaration of trust restricting the ownership and transfer of its shares of beneficial interest are described in "Description of Our Shares—Restrictions on Ownership and Transfer."

For purposes of determining share ownership under requirement 6, an "individual" generally includes a supplemental unemployment compensation benefits plan, a private foundation, or a portion of a trust permanently set aside or used exclusively for charitable purposes. An "individual," however, generally does not include a trust that is a qualified employee pension or profit sharing trust under the federal income tax laws, and beneficiaries of such a trust will be treated as holding CubeSmart's shares in proportion to their actuarial interests in the trust for purposes of requirement 6. CubeSmart believes it has issued sufficient shares of beneficial interest with enough diversity of ownership to satisfy requirements 5 and 6 set forth above.

To monitor compliance with the share ownership requirements, CubeSmart is required to maintain records regarding the actual ownership of its shares. To do so, CubeSmart must demand written statements each year from the record holders of certain percentages of its shares in which the record holders are to disclose the actual owners of the shares (the persons required to include in gross income the dividends paid by us). A list of those persons failing or refusing to comply with this demand must be maintained as part of CubeSmart's records. Failure by CubeSmart to comply with these record-keeping requirements could subject CubeSmart to monetary penalties. If CubeSmart satisfies these requirements and has no reason to know that condition (6) is not satisfied, CubeSmart will be deemed to have satisfied such condition. A shareholder that fails or refuses to comply with the demand is required by Treasury Regulations to submit a statement with its tax return disclosing the actual ownership of the shares and other information.

Qualified REIT Subsidiaries. A corporation that is a "qualified REIT subsidiary" is not treated as a corporation separate from its parent REIT. A "qualified REIT subsidiary" is a corporation, all of the capital stock of which is owned by the REIT and that has not elected to be a taxable REIT subsidiary. All assets, liabilities, and items of income, deduction, and credit of a "qualified REIT subsidiary" are treated as assets, liabilities, and items of income, deduction, and credit of the REIT. Thus, in applying the requirements described herein, any "qualified REIT subsidiary" that CubeSmart owns will be ignored, and all assets, liabilities, and items of income, deduction, and credit of such subsidiary will be treated as its assets, liabilities, and items of income, deduction, and credit.

Partnership Subsidiaries. An unincorporated domestic entity, such as a partnership or limited liability company that has a single owner, generally is not treated as an entity separate from its parent for federal income tax purposes. An unincorporated domestic entity with two or more owners is generally treated as a partnership for federal income tax purposes. In the case of a REIT that is a partner in a partnership, the REIT is treated as owning its proportionate share of the assets of the partnership and as earning its allocable share of the gross income of the partnership for purposes of the applicable REIT qualification tests. Thus, CubeSmart's proportionate share of the assets, liabilities and items of income of the Operating Partnership and any other partnership, joint venture, or limited liability company that is treated as a partnership for federal income tax purposes in which CubeSmart acquires an interest, directly or indirectly, is treated as CubeSmart's assets and gross income for purposes of applying the various REIT qualification requirements.

Taxable REIT Subsidiaries. A REIT is permitted to own up to 100% of the stock of one or more "taxable REIT subsidiaries." A taxable REIT subsidiary is a corporation subject to U.S. federal income tax, and state and local income tax where applicable, as a regular "C" corporation. The subsidiary and the REIT must jointly elect to treat the subsidiary as a taxable REIT subsidiary. In addition, if a taxable REIT subsidiary owns, directly or indirectly, securities representing 35% or more of the vote or value of a subsidiary corporation, that subsidiary will also be treated as a taxable REIT subsidiary. Several provisions regarding the arrangements between a REIT and its taxable REIT subsidiaries ensure that a taxable REIT subsidiary will be subject to an appropriate level of United States federal income taxation. For example, the taxable REIT subsidiary rules limit the deductibility of interest paid or accrued by a taxable REIT subsidiary to its parent REIT. Further, the rules impose a 100% excise tax on transactions between a taxable REIT subsidiary and its parent REIT or the REIT's tenants that are not conducted on an arm's-length basis. CubeSmart may engage in activities indirectly through a taxable REIT subsidiary that would jeopardize its REIT status if CubeSmart engaged in the activities directly. For example, a taxable REIT subsidiary of CubeSmart may provide services to unrelated parties which might produce income that does not qualify under the gross income tests described below. A taxable REIT subsidiary may also engage in other activities that, if conducted by CubeSmart directly, could result in the receipt of non-qualified income or the ownership of non-qualified assets or the imposition of the 100% tax on income from prohibited transactions. See description below under "Prohibited Transactions."

Gross Income Tests. CubeSmart must satisfy two gross income tests annually to maintain its qualification as a REIT. First, at least 75% of its gross income for each taxable year must consist of defined types of income that CubeSmart derives, directly or indirectly, from investments relating to real property or mortgages on real property or qualified temporary investment income. Qualifying income for purposes of that 75% gross income test generally includes:

Second, in general, at least 95% of CubeSmart's gross income for each taxable year must consist of income that is qualifying income for purposes of the 75% gross income test, other types of interest and dividends (including dividends from its taxable REIT subsidiaries), gain from the sale or disposition of stock or securities, or any combination of these. Gross income from the sale of property that CubeSmart holds primarily for sale to customers in the ordinary course of business is excluded from both the numerator and the denominator in both income tests. See "Prohibited Transactions." In addition, certain gains from hedging transactions and certain foreign currency gains will be excluded from both the numerator and the denominator for purposes of one or both of the income tests. See "Hedging Transactions," and "Foreign Currency Gain."

Rents from Real Property. Rent that CubeSmart receives from its real property will qualify as "rents from real property," which is qualifying income for purposes of the 75% and 95% gross income tests, only if the following conditions are met:

First, the rent must not be based in whole or in part on the income or profits of any person. Participating rent, however, will qualify as "rents from real property" if it is based on percentages of receipts or sales and the percentages are fixed at the time the leases are entered into, are not renegotiated during the term of the leases in a manner that has the effect of basing percentage rent on income or profits, and conform with normal business practice.

Second, CubeSmart must not own, actually or constructively, 10% or more of the stock of any corporate tenant or the assets or net profits of any tenant, referred to as a related party tenant, other than a taxable REIT subsidiary. The constructive ownership rules generally provide that, if 10% or more in value of its shares is owned, directly or indirectly, by or for any person, CubeSmart is considered as owning the stock owned, directly or indirectly, by or for such person. CubeSmart does not own any stock or any assets or net profits of any tenant directly. However, because the constructive ownership rules are broad and it is not possible to monitor continually direct and indirect transfers of its shares, no absolute assurance can be given that such transfers or other events of which CubeSmart has no knowledge will not cause CubeSmart to own constructively 10% or more of a tenant (or a subtenant, in which case only rent attributable to the subtenant is disqualified) other than a taxable REIT subsidiary at some future date.

Under an exception to the related-party tenant rule described in the preceding paragraph, rent that CubeSmart receives from a taxable REIT subsidiary will qualify as "rents from real property" as long as (1) at least 90% of the leased space in the property is leased to persons other than taxable REIT subsidiaries and related-party tenants, and (2) the amount paid by the taxable REIT subsidiary to rent space at the property is substantially comparable to rents paid by other tenants of the property for comparable space. The "substantially comparable" requirement must be satisfied when the lease is entered into, when it is extended, and when the lease is modified, if the modification increases the rent paid by the taxable REIT subsidiary. If the requirement that at least 90% of the leased space in the related property is rented to unrelated tenants is met when a lease is entered into, extended, or modified, such requirement will continue to be met as long as there is no increase in the space leased to any taxable REIT subsidiary or related party tenant. Any increased rent attributable to a

modification of a lease with a taxable REIT subsidiary in which CubeSmart owns directly or indirectly more than 50% of the voting power or value of the stock (a "controlled taxable REIT subsidiary") will not be treated as "rents from real property."

Third, the rent attributable to the personal property leased in connection with a lease of real property must not be greater than 15% of the total rent received under the lease. The rent attributable to personal property under a lease is the amount that bears the same ratio to total rent under the lease for the taxable year as the average of the fair market values of the leased personal property at the beginning and at the end of the taxable year bears to the average of the aggregate fair market values of both the real and personal property covered by the lease at the beginning and at the end of such taxable year (the "personal property ratio"). With respect to each of its leases, CubeSmart believes that the personal property ratio generally is less than 15%. Where that is not, or may in the future not be, the case, CubeSmart believes that any income attributable to personal property will not jeopardize its ability to qualify as a REIT. There can be no assurance, however, that the Internal Revenue Service would not challenge CubeSmart's calculation of a personal property ratio, or that a court would not uphold such assertion. If such a challenge were successfully asserted, CubeSmart could fail to satisfy the 75% or 95% gross income test and thus lose its REIT status.

Fourth, CubeSmart cannot furnish or render non-customary services to the tenants of its properties, or manage or operate its properties, other than through an independent contractor who is adequately compensated and from whom CubeSmart does not derive or receive any income. However, CubeSmart need not provide services through an "independent contractor," but instead may provide services directly to its tenants, if the services are "usually or customarily rendered" in connection with the rental of space for occupancy only and are not considered to be provided for the tenants' convenience. In addition, CubeSmart may provide a minimal amount of "non-customary" services to the tenants of a property, other than through an independent contractor, as long as its income from the services does not exceed 1% of its income from the related property. Finally, CubeSmart may own up to 100% of the stock of one or more taxable REIT subsidiaries, which may provide non-customary services to CubeSmart's tenants without tainting CubeSmart's rents from the related properties. CubeSmart has not performed, and does not intend to perform, any services other than customary ones for its tenants, other than services provided through independent contractors or taxable REIT subsidiaries.

Tenants may be required to pay, in addition to base rent, reimbursements for certain amounts CubeSmart is obligated to pay to third parties (such as a lessee's proportionate share of a property's operational or capital expenses), penalties for nonpayment or late payment of rent or additions to rent. These and other similar payments should qualify as "rents from real property." To the extent they do not, they should be treated as interest that qualifies for the 95% gross income test.

If a portion of the rent CubeSmart receives from a property does not qualify as "rents from real property" because the rent attributable to personal property exceeds 15% of the total rent for a taxable year, the portion of the rent attributable to personal property will not be qualifying income for purposes of either the 75% or 95% gross income test. Thus, if rent attributable to personal property, plus any other income that is nonqualifying income for purposes of the 95% gross income test, during a taxable year exceeds 5% of its gross income during the year, CubeSmart would lose its REIT status, unless CubeSmart qualified for certain statutory relief provisions. By contrast, in the following circumstances, none of the rent from a lease of property would qualify as "rents from real property": (1) the rent is considered based on the income or profits of the tenant; (2) the lessee is a related party tenant or fails to qualify for the exception to the related-party tenant rule for qualifying taxable REIT subsidiaries; or (3) CubeSmart furnishes non-customary services to the tenants of the property, or manages or operates the property, other than through a qualifying independent contractor or a taxable REIT subsidiary. In any of these circumstances, CubeSmart could lose its REIT status, unless

CubeSmart qualified for certain statutory relief provisions, because it would be unable to satisfy either the 75% or 95% gross income test.

Interest. The term "interest" generally does not include any amount received or accrued, directly or indirectly, if the determination of the amount depends in whole or in part on the income or profits of any person. However, an amount received or accrued generally will not be excluded from the term "interest" solely because it is based on a fixed percentage or percentages of receipts or sales. Furthermore, to the extent that interest from a loan that is based on the profit or net cash proceeds from the sale of the property securing the loan constitutes a "shared appreciation provision," income attributable to such participation feature will be treated as gain from the sale of the secured property.

Prohibited Transactions. A REIT will incur a 100% tax on the net income derived from any sale or other disposition of property, other than foreclosure property, that the REIT holds primarily for sale to customers in the ordinary course of a trade or business. Whether a REIT holds an asset "primarily for sale to customers in the ordinary course of a trade or business" depends, however, on the facts and circumstances in effect from time to time, including those related to a particular asset. A safe harbor to the characterization of the sale of property by a REIT as a prohibited transaction and the 100% prohibited transaction tax is available if the following requirements are met:

CubeSmart intends to hold properties for investment with a view to long-term appreciation, to engage in the business of acquiring, developing, owning and operating properties, and to make occasional sales of properties as are consistent with its investment objective. CubeSmart cannot assure you; however, that it can comply with the safe-harbor provisions that would prevent the imposition of the 100% tax or that it will avoid owning property that may be characterized as property held "primarily for sale to customers in the ordinary course of a trade or business." The 100% tax does not apply to gains from the sale of property that is held through a taxable REIT subsidiary or other taxable corporation, although such income will be subject to tax in the hands of that corporation at regular corporate tax rates. CubeSmart may, therefore, form or acquire a taxable REIT subsidiary to hold and dispose of those properties it concludes may not fall within the safe-harbor provisions.

Foreclosure Property. CubeSmart will be subject to tax at the maximum corporate rate on any net income from foreclosure property, other than income that otherwise would be qualifying income for purposes of the 75% gross income test. "Foreclosure property" is any real property, including interests in real property, and any personal property incident to such real property:

A REIT will not be considered to have foreclosed on a property where the REIT takes control of the property as a mortgagee-in-possession and cannot receive any profit or sustain any loss except as a creditor of the mortgagor. Property generally ceases to be foreclosure property at the end of the third taxable year following the taxable year in which the REIT acquired the property (or longer if an extension is granted by the Secretary of the Treasury). This period (as extended, if applicable) terminates, and foreclosure property ceases to be foreclosure property on the first day:

Any gain from the sale of property for which a foreclosure property election has been made will not be subject to the 100% tax on gains from prohibited transactions described above, even if the property is held primarily for sale to customers in the ordinary course of a trade or business. Income and gain from foreclosure property are qualifying income for the 75% and 95% gross income tests.

Hedging Transactions. From time to time, CubeSmart enters into hedging transactions with respect to its assets or liabilities. CubeSmart's hedging activities may include entering into interest rate swaps, caps, and floors, options to purchase such items, and futures and forward contracts. For hedging transactions entered into on or before July 30, 2008, income and gain from "hedging transactions" will be excluded from gross income for purposes of the 95% gross income test, but not the 75% gross income test. For hedging transactions entered into after July 30, 2008, income and gain from "hedging transactions" will be excluded from gross income for purposes of both the 75% and 95% gross income tests. A "hedging transaction" means either (1) any transaction entered into in the normal course of its trade or business primarily to manage the risk of interest rate, price changes, or currency fluctuations with respect to borrowings made or to be made, or ordinary obligations incurred or to be incurred, to acquire or carry real estate assets or (2) for transactions entered into after July 30, 2008, any transaction entered into primarily to manage the risk of currency fluctuations with respect to any item of income or gain that would be qualifying income under the 75% or 95% gross income test (or any property which generates such income or gain). CubeSmart will be required to clearly identify any such hedging transaction before the close of the day on which it was acquired, originated, or entered into and to satisfy other identification requirements. No assurance can be given that its hedging activities will not give rise to income that does not qualify for purposes of either or both of the gross income tests, and will not adversely affect CubeSmart's ability to satisfy the REIT qualification requirements.

Foreign Currency Gain. Certain foreign currency gains recognized after July 30, 2008 will be excluded from gross income for purposes of one or both of the gross income tests. "Real estate foreign exchange gain" will be excluded from gross income for purposes of the 75% gross income test. Real estate foreign exchange gain generally includes foreign currency gain attributable to any item of income or gain that is qualifying income for purposes of the 75% gross income test, foreign currency gain attributable to the acquisition or ownership of (or becoming or being the obligor under) obligations secured by mortgages on real property or on interest in real property and certain foreign currency gain attributable to certain "qualified business units" of a REIT. "Passive foreign exchange gain" will be excluded from gross income for purposes of the 95% gross income test. Passive foreign exchange gain generally includes real estate foreign exchange gain as described above, and also includes foreign currency gain attributable to any item of income or gain that is qualifying income for purposes of the 95% gross income test and foreign currency gain attributable to the acquisition or ownership of (or becoming or being the obligor under) obligations secured by mortgages on real property or on interest in real property. Because passive foreign exchange gain includes real estate foreign exchange gain, real estate foreign exchange gain is excluded from gross income for purposes of both the 75% and 95% gross income test. These exclusions for real estate foreign exchange gain and passive foreign exchange gain do not apply to foreign currency gain derived from dealing, or engaging in substantial and regular trading, in securities. Such gain is treated as nonqualifying income for purposes of both the 75% and 95% gross income tests.

Failure to Satisfy Gross Income Tests. If CubeSmart fails to satisfy one or both of the gross income tests for any taxable year, CubeSmart nevertheless may qualify as a REIT for that year if it qualifies for relief under certain provisions of the federal income tax laws. Those relief provisions will be available if:

CubeSmart cannot predict, however, whether any failure to meet these tests will qualify for the relief provisions. As discussed above in "Taxation of CubeSmart as a REIT," even if the relief provisions apply, CubeSmart would incur a 100% tax on the gross income attributable to the greater of (1) the amount by which it fails the 75% gross income test, or (2) the excess of 95% of its gross income over the amount of gross income qualifying under the 95% gross income test, multiplied, in either case, by a fraction intended to reflect its profitability.

Asset Tests. To maintain its qualification as a REIT, CubeSmart also must satisfy the following asset tests at the end of each quarter of each taxable year.

Second, of CubeSmart's investments not included in the 75% asset class, the value of its interest in any one issuer's securities may not exceed 5% of the value of its total assets, or the "5% asset test".

Third, of CubeSmart's investments not included in the 75% asset class, CubeSmart may not own more than 10% of the voting power or value of any one issuer's outstanding securities, or the "10% vote test" and "10% value test", respectively.

Fourth, no more than 20% of the value of CubeSmart's total assets (or, beginning with its 2009 taxable year, 25% of the value of its total assets) may consist of the securities of one or more taxable REIT subsidiaries..

For purposes of the 5% asset test, the 10% vote test and 10% value test, the term "securities" does not include stock in another REIT, equity or debt securities of a qualified REIT subsidiary or taxable REIT subsidiary, mortgage loans that constitute real estate assets, or equity interests in a partnership. The term "securities," however, generally includes debt securities issued by a partnership or another REIT, except that for purposes of the 10% value test, the term "securities" does not include:

Failure to Satisfy Asset Tests. CubeSmart will monitor the status of its assets for purposes of the various asset tests and will manage its portfolio in order to comply at all times with such tests. If CubeSmart fails to satisfy the asset tests at the end of a calendar quarter, it would not lose its REIT status if:

If the failure to satisfy the asset tests results from an acquisition of securities or other property during a quarter, the failure can be cured by disposition of sufficient nonqualifying assets within 30 days after the close of that quarter. CubeSmart intends to maintain adequate records of the value of its assets to ensure compliance with the asset tests, and to take such other action within 30 days after the close of any quarter as may be required to cure any noncompliance. However, there can be no assurance that such other action will always be successful. If CubeSmart fails to cure any noncompliance with the asset tests within such time period, its status as a REIT would be lost.

In the event that, at the end of any calendar quarter, CubeSmart violates the 5% asset test, the 10% vote test or the 10% value test described above, CubeSmart will not lose its REIT status if (i) the failure is de minimis (up to the lesser of 1% of its assets or $10 million) and (ii) CubeSmart disposes of assets or otherwise complies with the asset tests within six months after the last day of the quarter in which it identifies such failure. In the event the failure to meet the asset test is more than de minimis, CubeSmart will not lose its REIT status if (i) the failure was due to reasonable cause and not to willful neglect, (ii) CubeSmart files a description of each asset causing the failure with the Internal Revenue Service, (iii) CubeSmart disposes of assets or otherwise comply with the asset tests within six months after the last day of the quarter in which CubeSmart identifies the failure, and (iv) CubeSmart pays a tax equal to the greater of $50,000 or 35% of the net income from the nonqualifying assets during the period in which it failed to satisfy the asset tests.

Annual Distribution Requirements. Each taxable year, CubeSmart must distribute dividends, other than capital gain dividends and deemed distributions of retained capital gain, to its shareholders in an aggregate amount not less than the sum of

Generally, CubeSmart must pay such distributions in the taxable year to which they relate, or in the following taxable year if either (a) CubeSmart declares the distribution before it timely files its federal income tax return for the year and pays the distribution on or before the first regular dividend payment date after such declaration or (b) CubeSmart declares the distribution in October, November, or December of the taxable year, payable to shareholders of record on a specified day in any such month, and CubeSmart actually pays the dividend before the end of January of the following year. In both instances, these distributions relate to its prior taxable year for purposes of the 90% distribution requirement.

In order for distributions to be counted towards CubeSmart's distribution requirement, and to provide a tax deduction to CubeSmart, they must not be "preferential dividends." A dividend is not a preferential dividend if it is pro rata among all outstanding shares within a particular class, and is in accordance with the preferences among the different classes of shares as set forth in CubeSmart's organizational documents.

To the extent that CubeSmart distributes at least 90%, but less than 100%, of its net taxable income, CubeSmart will be subject to tax at ordinary corporate tax rates on the retained portion. In addition, CubeSmart may elect to retain, rather than distribute, its net long-term capital gains and pay tax on such gains. In this case, CubeSmart would elect to have its shareholders include their proportionate share of such undistributed long-term capital gains in their income and receive a corresponding credit for their proportionate share of the tax paid by us. CubeSmart's shareholders would then increase their adjusted basis in their CubeSmart shares by the difference between the amount included in their long-term capital gains and the tax deemed paid with respect to their shares.

If CubeSmart fails to distribute during a calendar year, or by the end of January of the following calendar year in the case of distributions with declaration and record dates falling in the last three months of the calendar year, at least the sum of:

It is possible that, from time to time, CubeSmart may experience timing differences between the actual receipt of income and actual payment of deductible expenses and the inclusion of that income and deduction of such expenses in arriving at its REIT taxable income. For example, because CubeSmart may deduct capital losses only to the extent of its capital gains, its REIT taxable income may exceed its economic income. Further, it is possible that, from time to time, CubeSmart may be allocated a share of net capital gain from a partnership in which CubeSmart owns an interest attributable to the sale of depreciated property that exceeds its allocable share of cash attributable to that sale. Although several types of non-cash income are excluded in determining the annual distribution requirement, CubeSmart will incur corporate income tax and the 4% nondeductible excise tax with respect to those non-cash income items if CubeSmart does not distribute those items on a current basis. As a result of the foregoing, CubeSmart may have less cash than is necessary to distribute all of its taxable income and thereby avoid corporate income tax and the 4% nondeductible excise tax imposed on certain undistributed income. In such a situation, CubeSmart may issue additional common or preferred shares, CubeSmart may borrow or may cause the Operating Partnership to arrange for short-term or possibly long-term borrowing to permit the payment of required distributions, or CubeSmart may pay dividends in the form of taxable in-kind distributions of property, including potentially, its shares.

Under certain circumstances, CubeSmart may be able to correct a failure to meet the distribution requirement for a year by paying "deficiency dividends" to its shareholders in a later year. CubeSmart may include such deficiency dividends in its deduction for dividends paid for the earlier year. Although CubeSmart may be able to avoid income tax on amounts distributed as deficiency dividends, CubeSmart will be required to pay interest to the Internal Revenue Service based upon the amount of any deduction it takes for deficiency dividends.

Recordkeeping Requirements. CubeSmart must maintain certain records in order to qualify as a REIT. In addition, to avoid paying a penalty, CubeSmart must request on an annual basis information from its shareholders designed to disclose the actual ownership of its outstanding common shares.

If CubeSmart were to fail to qualify as a REIT in any taxable year and no relief provision applied, CubeSmart would have the following consequences: CubeSmart would be subject to federal income tax

and any applicable alternative minimum tax at regular corporate rates applicable to regular C corporations on its taxable income, determined without reduction for amounts distributed to shareholders. CubeSmart would not be required to make any distributions to shareholders. Unless CubeSmart qualified for relief under specific statutory provisions, it would not be permitted to elect taxation as a REIT for the four taxable years following the year during which CubeSmart ceased to qualify as a REIT.

If CubeSmart fails to satisfy one or more requirements for REIT qualification, other than the gross income tests and the asset tests, CubeSmart could avoid disqualification if its failure is due to reasonable cause and not to willful neglect and CubeSmart pays a penalty of $50,000 for each such failure. In addition, there are relief provisions for a failure of the gross income tests and asset tests, as described in "Requirements for Qualification—Gross Income Tests" and "Requirements for Qualification—Asset Tests." It is not possible to state whether in all circumstances CubeSmart would be entitled to such statutory relief.

We may be subject to taxation by various states and localities, including those in which we transact business or own property. The state and local tax treatment in such jurisdictions may differ from the federal income tax treatment described above.

The following discussion summarizes certain federal income tax considerations applicable to CubeSmart's direct or indirect investment in its Operating Partnership and any subsidiary partnerships or limited liability companies we form or acquire that are treated as partnerships for federal income tax purposes, each individually referred to as a "Partnership" and, collectively, as "Partnerships." The following discussion does not address state or local tax laws or any federal tax laws other than income tax laws.

Classification as Partnerships. CubeSmart is required to include in its income its distributive share of each Partnership's income and to deduct its distributive share of each Partnership's losses but only if such Partnership is classified for federal income tax purposes as a partnership (or an entity that is disregarded for federal income tax purposes if the entity has only one owner or member), rather than as a corporation or an association taxable as a corporation.

An organization with at least two owners or members will be classified as a partnership, rather than as a corporation, for federal income tax purposes if it:

Under the check-the-box regulations, an unincorporated domestic entity with at least two owners or members may elect to be classified either as an association taxable as a corporation or as a partnership. If such an entity does not make an election, it generally will be treated as a partnership for federal income tax purposes. We intend that each Partnership will be classified as a partnership for federal income tax purposes (or else a disregarded entity where there are not at least two separate beneficial owners).

A publicly traded partnership is a partnership whose interests are traded on an established securities market or are readily tradable on a secondary market (or a substantial equivalent). A publicly traded partnership is generally treated as a corporation for federal income tax purposes, but will not be so treated if, for each taxable year beginning after December 31, 1987 in which it was classified as a

publicly traded partnership, at least 90% of the partnership's gross income consisted of specified passive income, including real property rents (which includes rents that would be qualifying income for purposes of the 75% gross income test, with certain modifications that make it easier for the rents to qualify for the 90% passive income exception), gains from the sale or other disposition of real property, interest, and dividends (the "90% passive income exception").

Treasury regulations, referred to as PTP regulations, provide limited safe harbors from treatment as a publicly traded partnership. Pursuant to one of those safe harbors (the "private placement exclusion"), interests in a partnership will not be treated as readily tradable on a secondary market or the substantial equivalent thereof if (1) all interests in the partnership were issued in a transaction or transactions that were not required to be registered under the Securities Act of 1933, as amended, and (2) the partnership does not have more than 100 partners at any time during the partnership's taxable year. For the determination of the number of partners in a partnership, a person owning an interest in a partnership, grantor trust, or S corporation that owns an interest in the partnership is treated as a partner in the partnership only if (1) substantially all of the value of the owner's interest in the entity is attributable to the entity's direct or indirect interest in the partnership and (2) a principal purpose of the use of the entity is to permit the partnership to satisfy the 100-partner limitation. CubeSmart believes that each Partnership should qualify for the private placement exclusion.

We have not requested, and do not intend to request, a ruling from the Internal Revenue Service that the Partnerships will be classified as partnerships (or disregarded entities, if the entity has only one owner or member) for federal income tax purposes. If for any reason a Partnership were taxable as a corporation, rather than as a partnership, for federal income tax purposes, CubeSmart may not be able to qualify as a REIT, unless it qualifies for certain relief provisions. See "Requirements for Qualification—Gross Income Tests" and "Requirements for Qualification—Asset Tests." In addition, any change in a Partnership's status for tax purposes might be treated as a taxable event, in which case CubeSmart might incur tax liability without any related cash distribution. See "Requirements for Qualification—Annual Distribution Requirements." Further, items of income and deduction of such Partnership would not pass through to its partners, and its partners would be treated as shareholders for tax purposes. Consequently, such Partnership would be required to pay income tax at corporate rates on its net income, and distributions to its partners would constitute dividends that would not be deductible in computing such Partnership's taxable income.

Partners, Not the Partnerships, Subject to Tax. A partnership is not a taxable entity for federal income tax purposes. CubeSmart will therefore take into account its allocable share of each Partnership's income, gains, losses, deductions, and credits for each taxable year of the Partnership ending with or within CubeSmart's taxable year, even if CubeSmart receives no distribution from the Partnership for that year or a distribution less than CubeSmart's share of taxable income. Similarly, even if CubeSmart receives a distribution, CubeSmart may not be taxable if the distribution does not exceed its adjusted tax basis in its interest in the Partnership.

Partnership Allocations. Although a partnership agreement generally will determine the allocation of income and losses among partners, allocations will be disregarded for tax purposes if they do not comply with the provisions of the federal income tax laws governing partnership allocations. If an allocation is not recognized for federal income tax purposes, the item subject to the allocation will be reallocated in accordance with the partners' interests in the partnership, which will be determined by taking into account all of the facts and circumstances relating to the economic arrangement of the partners with respect to such item.

Tax Allocations With Respect to Contributed Properties. Income, gain, loss, and deduction attributable to (a) appreciated or depreciated property that is contributed to a partnership in exchange for an interest in the partnership or (b) property revalued on the books of a partnership must be allocated in a manner such that the contributing partner is charged with, or benefits from, respectively, the unrealized gain or unrealized loss associated with the property at the time of the contribution. The amount of such unrealized gain or unrealized loss, referred to as "built-in gain" or "built-in loss," is generally equal to the difference between the fair market value of the contributed or revalued property at the time of contribution or revaluation and the adjusted tax basis of such property at that time, referred to as a book-tax difference. Such allocations are solely for federal income tax purposes and do not affect the book capital accounts or other economic or legal arrangements among the partners. The U.S. Treasury Department has issued regulations requiring partnerships to use a "reasonable method" for allocating items with respect to which there is a book-tax difference and outlining several reasonable allocation methods. Unless we, as general partner, select a different method, the Operating Partnership will use the traditional method for allocating items with respect to which there is a book-tax difference. Depending upon the method chosen, (1) CubeSmart's tax depreciation deductions attributable to those properties may be lower than they would have been if the partnership had acquired those properties for cash and (2) in the event of a sale of such properties, CubeSmart could be allocated gain in excess of its corresponding economic or book gain. These allocations may cause CubeSmart to recognize taxable income in excess of cash proceeds received by us, which might adversely affect CubeSmart's ability to comply with the REIT distribution requirements or result in CubeSmart's shareholders recognizing additional dividend income without an increase in distributions.

Depreciation. Some assets in our Partnerships include appreciated property contributed by its partners. Assets contributed to a Partnership in a tax-free transaction generally retain the same depreciation method and recovery period as they had in the hands of the partner who contributed them to the partnership. Accordingly, the Partnership's depreciation deductions for such contributed real property are based on the historic tax depreciation schedules for the properties prior to their contribution to the Operating Partnership.

Basis in Partnership Interest. CubeSmart's adjusted tax basis in any partnership interest it owns generally will be:

Loss allocated to CubeSmart in excess of its basis in a partnership interest will not be taken into account until CubeSmart again has basis sufficient to absorb the loss. A reduction of CubeSmart's share of partnership indebtedness will be treated as a constructive cash distribution to CubeSmart, and will reduce its adjusted tax basis in the partnership. Distributions, including constructive distributions, in excess of the basis of CubeSmart's partnership interest will constitute taxable income to CubeSmart. Such distributions and constructive distributions normally will be characterized as long-term capital gain.

Sale of a Partnership's Property. Generally, any gain realized by a Partnership on the sale of property held for more than one year will be long-term capital gain, except for any portion of the gain treated as depreciation or cost recovery recapture. Any gain or loss recognized by a Partnership on the disposition of contributed or revalued properties will be allocated first to the partners who contributed

the properties or who were partners at the time of revaluation, to the extent of their built-in gain or loss on those properties for federal income tax purposes. The partners' built-in gain or loss on contributed or revalued properties is the difference between the partners' proportionate share of the book value of those properties and the partners' tax basis allocable to those properties at the time of the contribution or revaluation. Any remaining gain or loss recognized by the Partnership on the disposition of contributed or revalued properties, and any gain or loss recognized by the Partnership on the disposition of other properties, will be allocated among the partners in accordance with their percentage interests in the Partnership.

CubeSmart's share of any Partnership gain from the sale of inventory or other property held primarily for sale to customers in the ordinary course of the Partnership's trade or business will be treated as income from a prohibited transaction subject to a 100% tax. Income from a prohibited transaction may have an adverse effect on CubeSmart's ability to satisfy the gross income tests for REIT status. See "Requirements for Qualification—Gross Income Tests." CubeSmart does not presently intend to acquire or hold, or to allow any Partnership to acquire or hold, any property that is likely to be treated as inventory or property held primarily for sale to customers in the ordinary course of CubeSmart's, or the Partnership's, trade or business.

The term "U.S. shareholder" means a holder of CubeSmart common shares that, for U.S. federal income tax purposes, is:

If a partnership, entity or arrangement treated as a partnership for federal income tax purposes holds CubeSmart common shares, the federal income tax treatment of a partner in the partnership will generally depend on the status of the partner and the activities of the partnership. If you are a partner in a partnership holding CubeSmart common shares, you should consult your tax advisor regarding the consequences of the ownership and disposition of CubeSmart common shares by the partnership.

Taxation of U.S. Shareholders on Distributions. As long as CubeSmart qualifies as a REIT, a taxable U.S. shareholder will be required to take into account as ordinary income distributions made out of CubeSmart's current or accumulated earnings and profits that CubeSmart does not designate as capital gain dividends or retained long-term capital gain. A U.S. shareholder will not qualify for the dividends-received deduction generally available to corporations. Dividends paid to a U.S. shareholder generally will not qualify for the 15% tax rate for "qualified dividend income." The maximum tax rate for qualified dividend income to 15% for tax years through 2012. Without future congressional action, in 2013 the maximum tax rate on qualified dividend income will revert to the rate then applicable to ordinary income. Qualified dividend income generally includes dividends paid by domestic C corporations and certain qualified foreign corporations to most noncorporate U.S. shareholders. Because a REIT is not generally subject to federal income tax on the portion of its REIT taxable income distributed to its shareholders, CubeSmart's dividends generally will not be eligible for the

15% rate on qualified dividend income. As a result, CubeSmart's ordinary REIT dividends will be taxed at the higher rate applicable to ordinary income. Currently, the highest marginal individual income tax rate on ordinary income is 35%. However, the 15% tax rate for qualified dividend income will apply to CubeSmart's ordinary REIT dividends, if any, that are (i) attributable to dividends received by CubeSmart from non-REIT corporations, such as our taxable REIT subsidiaries, and (ii) attributable to income upon which CubeSmart has paid corporate income tax (e.g., to the extent that CubeSmart distributes less than 100% of CubeSmart's taxable income). In general, to qualify for the reduced tax rate on qualified dividend income, a U.S. shareholder must hold CubeSmart common shares for more than 60 days during the 121-day period beginning on the date that is 60 days before the date on which the common shares become ex-dividend.

CubeSmart may distribute taxable dividends that are payable partly in cash and partly in CubeSmart common shares. Taxable U.S. shareholders receiving such dividends will be required to include the full amount of the dividends as ordinary income to the extent of CubeSmart's current and accumulated earnings and profits.

Any distribution CubeSmart declares in October, November, or December of any year that is payable to a U.S. shareholder of record on a specified date in any of those months will be treated as paid by CubeSmart and received by the U.S. shareholder on December 31 of the year, provided CubeSmart actually pays the distribution during January of the following calendar year.

Distributions to a U.S. shareholder which CubeSmart designates as capital gain dividends will generally be treated as long-term capital gain, without regard to the period for which the U.S. shareholder has held its common shares. CubeSmart generally will designate its capital gain dividends as either 15% or 25% rate distributions. Without future congressional action, in 2013 the maximum tax rate on capital gain dividends will revert to 20%. A corporate U.S. shareholder, however, may be required to treat up to 20% of certain capital gain dividends as ordinary income.

CubeSmart may elect to retain and pay income tax on the net long-term capital gain that CubeSmart receives in a taxable year. In that case, a U.S. shareholder would be taxed on its proportionate share of CubeSmart's undistributed long-term capital gain. The U.S. shareholder would receive a credit or refund for its proportionate share of the tax CubeSmart paid. The U.S. shareholder would increase the basis in its common shares by the amount of its proportionate share of CubeSmart's undistributed long-term capital gain, minus its share of the tax CubeSmart paid.

A U.S. shareholder will not incur tax on a distribution in excess of CubeSmart's current and accumulated earnings and profits if the distribution does not exceed the adjusted basis of the U.S. shareholder's common shares. Instead, the distribution will reduce the adjusted basis of the shares, and any amount in excess of both CubeSmart's current and accumulated earnings and profits and the adjusted basis will be treated as capital gain, long-term if the shares have been held for more than one year, provided the shares are a capital asset in the hands of the U.S. shareholder.

Shareholders may not include in their individual income tax returns any of CubeSmart's net operating losses or capital losses. Instead, these losses are generally carried over by CubeSmart for potential offset against CubeSmart's future income. Taxable distributions from CubeSmart and gain from the disposition of common shares will not be treated as passive activity income; and, therefore, shareholders generally will not be able to apply any "passive activity losses," such as losses from certain types of limited partnerships in which the shareholder is a limited partner, against such income. In addition, taxable distributions from CubeSmart and gain from the disposition of common shares generally will be treated as investment income for purposes of the investment interest limitations. CubeSmart will notify shareholders after the close of its taxable year as to the portions of the distributions attributable to that year that constitute ordinary income, return of capital, and capital gain.

Taxation of U.S. Shareholders on the Disposition of Common Shares. In general, a U.S. shareholder who is not a dealer in securities must treat any gain or loss realized upon a taxable disposition of CubeSmart's common shares as long-term capital gain or loss if the U.S. shareholder has held the shares for more than one year, and otherwise as short-term capital gain or loss. In general, a U.S. shareholder will realize gain or loss in an amount equal to the difference between the sum of the fair market value of any property and the amount of cash received in such disposition and the U.S. shareholder's adjusted tax basis. A U.S. shareholder's adjusted tax basis generally will equal the U.S. shareholder's acquisition cost, increased by the excess of net capital gains deemed distributed to the U.S. shareholder less tax deemed paid by it and reduced by any returns of capital. However, a U.S. shareholder must treat any loss upon a sale or exchange of common shares held by such shareholder for six months or less as a long-term capital loss to the extent of capital gain dividends and any actual or deemed distributions from CubeSmart that such U.S. shareholder treats as long-term capital gain. All or a portion of any loss that a U.S. shareholder realizes upon a taxable disposition of common shares may be disallowed if the U.S. shareholder purchases other common shares within 30 days before or after the disposition.

If a U.S. shareholder recognizes a loss upon a subsequent disposition of CubeSmart shares in an amount that exceeds a prescribed threshold, it is possible that the provisions of Treasury Regulations involving "reportable transactions" could apply, with a resulting requirement to separately disclose the loss generating transactions to the IRS. While these regulations are directed towards "tax shelters," they are written broadly, and apply to transactions that would not typically be considered tax shelters. Significant penalties apply for failure to comply with these requirements. You should consult your tax advisors concerning any possible disclosure obligation with respect to the receipt or disposition of CubeSmart shares, or transactions that might be undertaken directly or indirectly by us. Moreover, you should be aware that CubeSmart and other participants in transactions involving CubeSmart (including our advisors) might be subject to disclosure or other requirements pursuant to these regulations.

The tax-rate differential between capital gain and ordinary income for non-corporate taxpayers may be significant. A taxpayer generally must hold a capital asset for more than one year for gain or loss derived from its sale or exchange to be treated as long-term capital gain or loss. The highest marginal individual income tax rate is currently 35% (which rate will apply for the period through December 31, 2012). The maximum tax rate on long-term capital gain applicable to U.S. shareholders taxed at individual rates is 15% through December 31, 2012. Without future congressional action, in 2013 the maximum tax rate on long term capital gains will revert to 20%. The maximum tax rate on long-term capital gain from the sale or exchange of "section 1250 property" (i.e., generally, depreciable real property) is 25% to the extent the gain would have been treated as ordinary income if the property were "section 1245 property" (i.e., generally, depreciable personal property). CubeSmart generally may designate whether a distribution CubeSmart designates as capital gain dividends (and any retained capital gain that CubeSmart is deemed to distribute) is taxable to non-corporate shareholders at a 15% or 25% rate. The characterization of income as capital gain or ordinary income may affect the deductibility of capital losses. A non-corporate taxpayer may deduct capital losses not offset by capital gains against its ordinary income only up to a maximum of $3,000 annually. A non-corporate taxpayer may carry unused capital losses forward indefinitely. A corporate taxpayer must pay tax on its net capital gain at corporate ordinary-income rates. A corporate taxpayer may deduct capital losses only to the extent of capital gains, with unused losses carried back three years and forward five years.

Information Reporting Requirements and Backup Withholding. CubeSmart will report to its shareholders and to the Internal Revenue Service the amount of distributions CubeSmart pays during each calendar year and the amount of tax it withholds, if any. A shareholder may be subject to backup withholding at a rate of up to 28% with respect to distributions unless the holder:

A shareholder who does not provide CubeSmart with its correct taxpayer identification number also may be subject to penalties imposed by the Internal Revenue Service. In addition, CubeSmart may be required to withhold a portion of capital gain distributions to any shareholders who fail to certify their non-foreign status to CubeSmart. Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against the shareholder's income tax liability, provided the required information is furnished to the Internal Revenue Service.

Tax-exempt entities, including qualified employee pension and profit sharing trusts and individual retirement accounts and annuities, generally are exempt from federal income taxation. However, they are subject to taxation on their "unrelated business taxable income." While many investments in real estate generate unrelated business taxable income, the Internal Revenue Service has issued a ruling that dividend distributions from a REIT to an exempt employee pension trust do not constitute unrelated business taxable income so long as the exempt employee pension trust does not otherwise use the shares of the REIT in an unrelated trade or business of the pension trust. Based on that ruling, amounts CubeSmart distributes to tax-exempt shareholders generally should not constitute unrelated business taxable income. However, if a tax-exempt shareholder were to finance its acquisition of common shares with debt, a portion of the income it received from CubeSmart would constitute unrelated business taxable income pursuant to the "debt-financed property" rules. Furthermore, social clubs, voluntary employee benefit associations, supplemental unemployment benefit trusts, and qualified group legal services plans that are exempt from taxation under special provisions of the federal income tax laws are subject to different unrelated business taxable income rules, which generally will require them to characterize distributions they receive from CubeSmart as unrelated business taxable income.

In certain circumstances, a qualified employee pension or profit-sharing trust that owns more than 10% of CubeSmart's shares of beneficial interest (by value) must treat a percentage of the dividends it receives from CubeSmart as unrelated business taxable income. Such percentage is equal to the gross income CubeSmart derives from an unrelated trade or business, determined as if CubeSmart were a pension trust, divided by its total gross income for the year in which it pays the dividends. This rule applies to a pension trust holding more than 10% of CubeSmart shares only if:

Certain restrictions on ownership and transfer of CubeSmart's shares should generally prevent a tax-exempt entity from owning more than 10% of the value of its shares, or CubeSmart from becoming a pension-held REIT.

Tax-exempt U.S. shareholders are urged to consult their tax advisor regarding the U.S. federal, state, local and foreign tax consequences of the acquisition, ownership and disposition of CubeSmart shares.

The term "non-U.S. shareholder" means a holder of CubeSmart common shares that is not a U.S. shareholder or a partnership (or an entity treated as a partnership for federal income tax purposes). The rules governing U.S. federal income taxation of non-U.S. shareholders are complex. This section is only a summary of such rules. We urge non-U.S. shareholders to consult their own tax advisors to determine the impact of federal, state, local and foreign income tax laws on ownership of common shares, including any reporting requirements.

Taxation of Distributions. A non-U.S. shareholder that receives a distribution which is not attributable to gain from CubeSmart's sale or exchange of a "United States real property interest" ("USRPI") (discussed below) and that CubeSmart does not designate a capital gain dividend or retained capital gain will recognize ordinary income to the extent that CubeSmart pays such distribution out of CubeSmart's current or accumulated earnings and profits. A withholding tax equal to 30% of the gross amount of the distribution ordinarily will apply unless an applicable tax treaty reduces or eliminates the tax. However, a non-U.S. shareholder generally will be subject to federal income tax at graduated rates on any distribution treated as effectively connected with the non-U.S. shareholder's conduct of a U.S. trade or business, in the same manner as U.S. shareholders are taxed on distributions. A corporate non-U.S. shareholder may, in addition, be subject to the 30% branch profits tax with respect to that distribution. CubeSmart plans to withhold U.S. income tax at the rate of 30% on the gross amount of any distribution paid to a non-U.S. shareholder unless either:

A non-U.S. shareholder will not incur tax on a distribution in excess of CubeSmart's current and accumulated earnings and profits if the excess portion of such distribution does not exceed the adjusted basis of its common shares. Instead, the excess portion of the distribution will reduce the adjusted basis of such shares. A non-U.S. shareholder will be subject to tax on a distribution that exceeds both CubeSmart's current and accumulated earnings and profits and the adjusted basis of its shares, if the non-U.S. shareholder otherwise would be subject to tax on gain from the sale or disposition of common shares, as described below. Because CubeSmart generally cannot determine at the time CubeSmart makes a distribution whether the distribution will exceed CubeSmart's current and accumulated earnings and profits, CubeSmart normally will withhold tax on the entire amount of any distribution at the same rate as CubeSmart would withhold on a dividend. However, a non-U.S. shareholder may obtain a refund of amounts CubeSmart withholds if CubeSmart later determines that a distribution in fact exceeded CubeSmart's current and accumulated earnings and profits.

CubeSmart may be required to withhold 10% of any distribution that exceeds CubeSmart's current and accumulated earnings and profits. Consequently, although CubeSmart intends to withhold at a rate of 30% on the entire amount of any distribution, to the extent CubeSmart does not do so, CubeSmart may withhold at a rate of 10% on any portion of a distribution not subject to withholding at a rate of 30%.

For any year in which CubeSmart qualifies as a REIT, except as discussed below with respect to 5% or less holders of regularly traded classes of shares, a non-U.S. shareholder will incur tax on distributions attributable to gain from CubeSmart's sale or exchange of a USRPI under the Foreign

Investment in Real Property Tax Act of 1980, or "FIRPTA". A USRPI includes certain interests in real property and shares in corporations at least 50% of whose assets consist of interests in real property. Under FIRPTA, a non-U.S. shareholder is taxed on distributions attributable to gain from sales of USRPIs as if the gain were effectively connected with the conduct of a U.S. business of the non-U.S. shareholder. A non-U.S. shareholder would be taxed on such a distribution at the normal capital gain rates applicable to U.S. shareholders, subject to applicable alternative minimum tax and a special alternative minimum tax in the case of a nonresident alien individual. A non-U.S. corporate shareholder not entitled to treaty relief or exemption also may be subject to the 30% branch profits tax on such a distribution. CubeSmart must withhold 35% of any distribution that CubeSmart could designate as a capital gain dividend. A non-U.S. shareholder may receive a credit against its tax liability for the amount CubeSmart withholds.

Capital gain distributions to the holders of CubeSmart common shares that are attributable to CubeSmart's sale of real property will be treated as ordinary dividends rather than as gain from the sale of a USRPI, as long as (i) CubeSmart's common shares continue to be "regularly traded" on an established securities market in the United States and (ii) the non-U.S. shareholder did not own more than 5% of CubeSmart's common shares any time during the one-year period prior to the distribution. As a result, non-U.S. shareholders owning 5% or less of CubeSmart's common shares generally would be subject to withholding tax on such capital gain distributions in the same manner as they are subject to withholding tax on ordinary dividends. If CubeSmart's common shares cease to be regularly traded on an established securities market in the United States or the non-U.S. shareholderowned more than 5% of CubeSmart's common shares any time during the one-year period prior to the distribution, capital gain distributions that are attributable to CubeSmart's sale of real property would be subject to tax under FIRPTA, as described in the preceding paragraph.

Taxation of Disposition of Shares. A non-U.S. shareholder generally will not incur tax under FIRPTA with respect to gain on a sale of common shares as long as CubeSmart is a "domestically-controlled REIT," which means that at all times non-U.S. persons hold, directly or indirectly, less than 50% in value of the outstanding common shares. CubeSmart cannot assure you that this test will be met. Further, even if CubeSmart is a domestically controlled REIT, pursuant to "wash sale" rules under FIRPTA, a non-U.S. shareholder may incur tax under FIRPTA. The "wash sale" rule applies to the extent such non-U.S. shareholder disposes of CubeSmart shares during the 30-day period preceding a dividend payment, and such non-U.S. shareholder (or a person related to such non-U.S. shareholder) acquires or enters into a contract or option to acquire CubeSmart common shares within 61 days of the 1st day of the 30 day period described above, and any portion of such dividend payment would, but for the disposition, be treated as a USRPI capital gain to such non-U.S. shareholder, then such non-U.S. shareholder shall be treated as having USRPI capital gain in an amount that, but for the disposition, would have been treated as USRPI capital gain.

In addition, a non-U.S. shareholder that owned, actually or constructively, 5% or less of the outstanding common shares at all times during a specified testing period will not incur tax under FIRPTA on gain from a sale of common shares if the shares are "regularly traded" on an established securities market. Because CubeSmart's common shares are "regularly traded" on an established securities market, CubeSmart expects that a non-U.S. shareholder generally will not incur tax under FIRPTA on gain from a sale of common shares unless it owns or has owned more than 5% of the common shares at any time during the five year period to such sale. Any gain subject to tax under FIRPTA will be treated in the same manner as it would be in the hands of U.S. shareholders, subject to alternative minimum tax, but under a special alternative minimum tax in the case of nonresident alien individuals, and the purchaser of the shares could be required to withhold 10% of the purchase price and remit such amount to the Internal Revenue Service.

A non-U.S. shareholder generally will incur tax on gain not subject to FIRPTA if:

Information Reporting and Backup Withholding Applicable to non-U.S. Shareholders. CubeSmart must report annually to the IRS and to each non-U.S. shareholder the amount of dividends paid to such holder and the tax withheld with respect to such dividends, regardless of whether withholding was required. Copies of the information returns reporting such dividends and withholding may also be made available to the tax authorities in the country in which the non-U.S. shareholder resides under the provisions of an applicable income tax treaty.

Payments of dividends or of proceeds from the disposition of shares made to a non-U.S. shareholder may be subject to information reporting and backup withholding unless such holder establishes an exemption, for example, by properly certifying its non-United States status on an IRS Form W-8 BEN or another appropriate version of IRS Form W-8. Notwithstanding the foregoing, backup withholding may apply if either CubeSmart or its paying agent has actual knowledge, or reason to know, that a non-U.S. shareholder is a United States person.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against the shareholder's income tax liability, provided the required information is furnished to the Internal Revenue Service.

The rules dealing with U.S. federal income taxation are constantly under review by persons involved in the legislative process and by the Internal Revenue Service and the U.S. Treasury Department. No assurance can be given as to whether, when, or in what form, the U.S. federal income tax laws applicable to CubeSmart and its shareholders may be enacted. Changes to the U.S. federal tax laws and interpretations of U.S. federal tax laws could adversely affect an investment in CubeSmart shares.

This section describes the material United States federal income tax consequences of owning the debt securities that the Operating Partnership may offer. This summary is for general information only and is not tax advice. The tax consequences of owning any particular issue of debt securities will be discussed in the applicable prospectus supplement.

As used herein, a "U.S. Holder" means a beneficial owner of debt securities of the Operating Partnership, who is, for U.S. federal income tax purposes:

If a partnership holds debt securities, the tax treatment of a partner will generally depend upon the status of the partner and the activities of the partnership. If you are a partner of a partnership holding debt securities of the Operating Partnership, you should consult your tax advisor regarding the consequences of the ownership and disposition of debt securities by the partnership..

Interest. The stated interest on debt securities generally will be taxable to a U.S. Holder as ordinary income at the time that it is paid or accrued, in accordance with the U.S. Holder's method of accounting for United States federal income tax purposes.

Original Issue Discount. If you own debt securities issued with original issue discount ("OID"), you will be subject to special tax accounting rules, as described in greater detail below. In that case, you should be aware that you generally must include OID in gross income in advance of the receipt of cash attributable to that income. However, you generally will not be required to include separately in income cash payments received on the debt securities, even if denominated as interest, to the extent those payments do not constitute "qualified stated interest," as defined below. If we determine that a particular debt security will be an OID debt security, we will disclose that determination in the prospectus relating to those debt securities.

A debt security with an "issue price" that is less than the "stated redemption price at maturity" (the sum of all payments to be made on the debt security other than "qualified stated interest") generally will be issued with OID if that difference is at least 0.25% of the stated redemption price at maturity multiplied by the number of complete years to maturity. The "issue price" of each debt security in a particular offering will be the first price at which a substantial amount of that particular offering is sold to the public. The term "qualified stated interest" means stated interest that is unconditionally payable in cash or in property, other than debt instruments of the issuer, and the interest to be paid meets all of the following conditions:

If we determine that particular debt securities of a series will bear interest that is not qualified stated interest, we will disclose that determination in the prospectus relating to those debt securities.

If you own a debt security issued with "de minimis" OID, which is discount that is not OID because it is less than 0.25% of the stated redemption price at maturity multiplied by the number of complete years to maturity, you generally must include the de minimis OID in income at the time principal payments on the debt securities are made in proportion to the amount paid. Any amount of de minimis OID that you have included in income will be treated as capital gain.

Certain of the debt securities may contain provisions permitting them to be redeemed prior to their stated maturity at our option and/or at your option. OID debt securities containing those features may be subject to rules that differ from the general rules discussed herein. If you are considering the purchase of OID debt securities with those features, you should carefully examine the applicable prospectus and should consult your own tax advisors with respect to those features since the tax consequences to you with respect to OID will depend, in part, on the particular terms and features of the debt securities.

If you own OID debt securities with a maturity upon issuance of more than one year you generally must include OID in income in advance of the receipt of some or all of the related cash payments using the "constant yield method" described in the following paragraphs. This method takes into account the compounding of interest.

The amount of OID that you must include in income if you are the initial United States holder of an OID debt security is the sum of the "daily portions" of OID with respect to the debt security for each day during the taxable year or portion of the taxable year in which you held that debt security ("accrued OID"). The daily portion is determined by allocating to each day in any "accrual period" a pro rata portion of the OID allocable to that accrual period. The "accrual period" for an OID debt security may be of any length and may vary in length over the term of the debt security, provided that each accrual period is no longer than one year and each scheduled payment of principal or interest occurs on the first day or the final day of an accrual period. The amount of OID allocable to any accrual period is an amount equal to the excess, if any, of:

OID allocable to a final accrual period is the difference between the amount payable at maturity, other than a payment of qualified stated interest, and the adjusted issue price at the beginning of the final accrual period. Special rules will apply for calculating OID for an initial short accrual period. The "adjusted issue price" of a debt security at the beginning of any accrual period is equal to its issue price increased by the accrued OID for each prior accrual period, determined without regard to the amortization of any acquisition or bond premium, as described below, and reduced by any payments made on the debt security (other than qualified stated interest) on or before the first day of the accrual period. Under these rules, you will generally have to include in income increasingly greater amounts of OID in successive accrual periods. We are required to provide information returns stating the amount of OID accrued on debt securities held of record by persons other than corporations and other exempt holders.

Floating rate debt securities are subject to special OID rules. In the case of an OID debt security that is a floating rate debt security, both the "yield to maturity" and "qualified stated interest" will be determined solely for purposes of calculating the accrual of OID as though the debt security will bear interest in all periods at a fixed rate generally equal to the rate that would be applicable to interest payments on the debt security on its date of issue or, in the case of certain floating rate debt securities, the rate that reflects the yield to maturity that is reasonably expected for the debt security. Additional rules may apply if either:

This discussion does not address the tax rules applicable to debt securities with an indexed principal amount. If you are considering the purchase of floating rate OID debt securities or securities with indexed principal amounts, you should carefully examine the prospectus relating to those debt securities, and should consult your own tax advisors regarding the United States federal income tax consequences to you of holding and disposing of those debt securities.

You may elect to treat all interest on any debt securities as OID and calculate the amount includible in gross income under the constant yield method described above. For purposes of this election, interest includes stated interest, acquisition discount, OID, de minimis OID, market discount, de minimis market discount and unstated interest, as adjusted by any amortizable bond premium or

acquisition premium. You must make this election for the taxable year in which you acquired the debt security, and you may not revoke the election without the consent of the Internal Revenue Service (the "IRS"). You should consult with your own tax advisors about this election.

Market Discount. If you purchase debt securities, other than OID debt securities, for an amount that is less than their stated redemption price at maturity, or, in the case of OID debt securities, their adjusted issue price, the amount of the difference will be treated as "market discount" for United States federal income tax purposes, unless that difference is less than a specified de minimis amount. Under the market discount rules, you will be required to treat any principal payment on, or any gain on the sale, exchange, retirement or other disposition of, the debt securities as ordinary income to the extent of the market discount that you have not previously included in income and are treated as having accrued on the debt securities at the time of their payment or disposition. In addition, you may be required to defer, until the maturity of the debt securities or their earlier disposition in a taxable transaction, the deduction of all or a portion of the interest expense on any indebtedness attributable to the debt securities. You may elect, on a debt security-by-debt security basis, to deduct the deferred interest expense in a tax year prior to the year of disposition. You should consult your own tax advisors before making this election.

Any market discount will be considered to accrue ratably during the period from the date of acquisition to the maturity date of the debt securities, unless you elect to accrue on a constant interest method. You may elect to include market discount in income currently as it accrues, on either a ratable or constant interest method, in which case the rule described above regarding deferral of interest deductions will not apply. Your election to include market discount in income currently, once made, applies to all market discount obligations acquired by you on or after the first taxable year to which your election applies and may not be revoked without the consent of the IRS. You should consult your own tax advisor before making this election.

Acquisition Premium and Amortizable Bond Premium. If you purchase OID debt securities for an amount that is greater than their adjusted issue price but equal to or less than the sum of all amounts payable on the debt securities after the purchase date other than payments of qualified stated interest, you will be considered to have purchased those debt securities at an "acquisition premium." Under the acquisition premium rules, the amount of OID that you must include in gross income with respect to those debt securities for any taxable year will be reduced by the portion of the acquisition premium properly allocable to that year.

If you purchase debt securities (including OID debt securities) for an amount in excess of the sum of all amounts payable on those debt securities after the purchase date other than qualified stated interest, you will be considered to have purchased those debt securities at a "premium" and, if they are OID debt securities, you will not be required to include any OID in income. You generally may elect to amortize the premium over the remaining term of those debt securities on a constant yield method as an offset to interest when includible in income under your regular accounting method. In the case of debt securities that provide for alternative payment schedules, bond premium is calculated by assuming that (a) you will exercise or not exercise options in a manner that maximizes your yield, and (b) we will exercise or not exercise options in a manner that minimizes your yield (except that we will be assumed to exercise call options in a manner that maximizes your yield). If you do not elect to amortize bond premium, that premium will decrease the gain or increase the loss you would otherwise recognize on disposition of the debt security. Your election to amortize premium on a constant yield method will also apply to all debt obligations held or subsequently acquired by you on or after the first day of the first taxable year to which the election applies. You may not revoke the election without the consent of the IRS. You should consult your own tax advisor before making this election.

Sale, Exchange and Retirement of Debt Securities. A U.S. Holder of debt securities will recognize gain or loss upon the sale, exchange, retirement, redemption or other taxable disposition of such debt securities in an amount equal to the difference between:

A U.S. Holder's adjusted tax basis in a debt security generally will equal the cost of the debt security to such holder (A) increased by the amount of OID or accrued market discount (if any) previously included in income by such holder and (B) decreased by the amount of any payments other than qualified stated interest payments and any amortizable bond premium taken by the holder.

Any gain or loss recognized will generally be capital gain or loss, and such capital gain or loss will generally be long-term capital gain or loss if debt securities has been held by the U.S. Holder for more than one year. Long-term capital gain for non-corporate taxpayers is subject to reduced rates of United States federal income taxation (15% maximum federal rate through the end of 2012). The deductibility of capital losses is subject to certain limitations.

If a U.S. Holder recognizes a loss upon a subsequent disposition of debt securities in an amount that exceeds a prescribed threshold, it is possible that the provisions of Treasury Regulations involving "reportable transactions" could apply, with a resulting requirement to separately disclose the loss generating transactions to the IRS. While these regulations are directed towards "tax shelters," they are written broadly, and apply to transactions that would not typically be considered tax shelters. Significant penalties apply for failure to comply with these requirements. You should consult your tax advisors concerning any possible disclosure obligation with respect to the receipt or disposition of debt securities, or transactions that might be undertaken directly or indirectly by us. Moreover, you should be aware that we and other participants in transactions involving us (including our advisors) might be subject to disclosure or other requirements pursuant to these regulations.

Assuming the debt security is debt for tax purposes, interest income accrued on the debt security should not constitute unrelated business taxable income to a tax-exempt holder. As a result, a tax-exempt holder generally should not be subject to U.S. federal income tax on the interest income accruing on debt securities of the Operating Partnership. Similarly, any gain recognized by the tax-exempt holder in connection with a sale of the debt security generally should not be unrelated business taxable income. However, if a tax-exempt holder were to finance its acquisition of the debt security with debt, a portion of the interest income and gain attributable to the debt security would constitute unrelated business taxable income pursuant to the "debt-financed property" rules. Tax-exempt holders should consult their own counsel to determine the potential tax consequences of an investment in debt securities of the Operating Partnership.

The term "non-U.S. Holder" means a holder of debt securities of the Operating Partnership that is not a U.S. Holder or a partnership (or an entity treated as a partnership for federal income tax purposes). The rules governing U.S. federal income taxation of non-U.S. Holders are complex. This section is only a summary of such rules. We urge non-U.S. Holders to consult their own tax advisors to determine the impact of federal, state, local and foreign income tax laws on ownership of debt securities, including any reporting requirements.

Interest. Interest (including OID) paid to a non-U.S. Holder of debt securities will not be subject to United States federal withholding tax under the "portfolio interest exception," provided that:

A payment of interest (including OID) to a non-U.S. Holder that does not qualify for the portfolio interest exception and that is not effectively connected to a United States trade or business will be subject to United States federal withholding tax at a rate of 30%, unless a United States income tax treaty applies to reduce or eliminate withholding.

A non-U.S. Holder will generally be subject to tax in the same manner as a U.S. Holder with respect to payments of interest (including OID) if such payments are effectively connected with the conduct of a trade or business by the non-U.S. Holder in the United States and, if an applicable tax treaty provides, such gain is attributable to a United States permanent establishment maintained by the non-U.S. Holder. In some circumstances, such effectively connected income received by a non-U.S. Holder which is a corporation may be subject to an additional "branch profits tax" at a 30% base rate or, if applicable, a lower treaty rate.

To claim the benefit of a lower treaty rate or to claim exemption from withholding because the income is effectively connected with a United States trade or business, the non-U.S. Holder must provide a properly executed IRS Form W-8BEN or IRS Form W-8ECI, or a suitable substitute form, as applicable, prior to the payment of interest. Such certificate must contain, among other information, the name and address of the non-U.S. Holder.

Non-U.S. Holders are urged to consult their own tax advisors regarding applicable income tax treaties, which may provide different rules.

Sale or Retirement of Debt Securities. A non-U.S. Holder generally will not be subject to United States federal income tax or withholding tax on gain realized on the sale, exchange or redemption of debt securities unless:

Except to the extent that an applicable tax treaty provides otherwise, a non-U.S. Holder will generally be subject to tax in the same manner as a U.S. Holder with respect to gain realized on the sale, exchange or redemption of debt securities if such gain is effectively connected with the conduct of a trade or business by the non-U.S. Holder in the United States and, if an applicable tax treaty provides, such gain is attributable to a United States permanent establishment maintained by the

non-U.S. Holder. In certain circumstances, a non-U.S. Holder that is a corporation will be subject to an additional "branch profits tax" at a 30% rate or, if applicable, a lower treaty rate on such income.

U.S. Federal Estate Tax. Your estate will not be subject to U.S. federal estate tax on the debt securities beneficially owned by you at the time of your death, provided that any payment to you on the debt securities, including OID, would be eligible for exemption from the 30% U.S. federal withholding tax under the "portfolio interest" rule described above, without regard to the certification requirement.

Information Reporting and Backup Withholding Applicable to Holders of Debt Securities

Certain U.S. Holders may be subject to information reporting requirements on payments of principal and interest (including OID) on debt securities and payments of the proceeds of the sale, exchange, or redemption of debt securities, and backup withholding, currently imposed at a rate of 28%, may apply to such payment if the U.S. Holder:

A non-U.S. Holder is generally not subject to backup withholding with respect to payments of interest (including OID) on debt securities if it certifies as to its status as a non-U.S. Holder under penalties of perjury or if it otherwise establishes an exemption, provided that neither we nor our paying agent has actual knowledge or reason to know that the non-U.S. Holder is a United States person or that the conditions of any other exemptions are not, in fact, satisfied. Information reporting requirements, however, will apply to payments of interest (including OID) to non-U.S. Holders where such interest is subject to withholding or exempt from United States withholding tax pursuant to a tax treaty. Copies of these information returns may also be made available under the provisions of a specific treaty or agreement to the tax authorities of the country in which the non-U.S. Holder resides.

The payment of the proceeds from the disposition of debt securities to or through the United States office of any broker, United States or foreign, will be subject to information reporting and possible backup withholding unless the owner certifies as to its non-United States status under penalties of perjury or otherwise establishes an exemption, provided that the broker does not have actual knowledge or reason to know that the non-U.S. Holder is a United States person or that the conditions of any other exemption are not, in fact, satisfied.

The payment of the proceeds from the disposition of debt securities to or through a non-United States office of a non-United States broker that is not a "United States related person" generally will not be subject to information reporting or backup withholding. For this purpose, a "United States related person" is:

In the case of the payment of proceeds from the disposition of debt securities to or through a non-United States office of a broker that is either a United States person or a United States related person, the payment may be subject to information reporting unless the broker has documentary evidence in its files that the owner is a non-U.S. Holder and the broker has no knowledge or reason to know to the contrary. Backup withholding will not apply to payments made through foreign offices of a broker that is a United States person or a United States related person, absent actual knowledge that the payee is a United States person.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from a payment to a Holder will be allowed as a refund or a credit against such Holder's United States federal income tax liability, provided that the requisite procedures are followed.

Holders of debt securities are urged to consult their tax advisors regarding their qualification for exemption from backup withholding and the procedure for obtaining such an exemption, if applicable.

On March 18, 2010 the President signed into law the Hiring Incentives to Restore Employment Act (the "HIRE Act"). The HIRE act may impose withholding taxes on certain types of payments made to "foreign financial institutions and "non-financial foreign entities" (as defined under these rules). The legislation imposes a 30% withholding tax on "withholdable payments," which include payments of dividends on CubeSmart common shares, payments of interest on debt securities of the Operating Partnership (without regard to the portfolio interest exception) or gross proceeds from the sale or other disposition of CubeSmart common shares or debt securities of the Operating Partnership paid to a foreign financial institution or to a non-financial foreign entity, unless (i) the foreign financial institution undertakes certain diligence and reporting obligations with respect to certain U.S. account holders or (ii) the non-financial foreign entity either certifies it does not have any substantial U.S. owners or furnishes identifying information regarding each substantial U.S. owner. If the payee is a foreign financial institution, it must enter into an agreement with the United States Treasury requiring, among other things, that it undertake to identify accounts held by certain U.S. persons or U.S.-owned foreign entities, annually report certain information about such accounts, and withhold 30% on payments to account holders whose actions prevent it from complying with these reporting and other requirements. The legislation would generally apply to payments made after December 31, 2012, other than with respect to payments on debentures that were issued prior to December 31, 2012. Prospective investors should consult their tax advisors regarding the possible implications of this legislation on their investment in CubeSmart common shares or debt securities of the Operating Partnership.

On March 30, 2010, the President signed into law the Health Care and Reconciliation Act of 2010 (the "Reconciliation Act"). The Reconciliation Act will require certain U.S. Shareholders who are individuals, estates or trusts and whose income exceeds certain thresholds to pay a 3.8% Medicare tax on "net investment income" which includes, among other things, dividends on shares, interest on debentures and capital gains from the sale or other disposition of shares or debentures, subject to certain exceptions. This tax will apply for taxable years beginning after December 31, 2012. U.S. shareholders should consult their tax advisors regarding the effect, if any, of this legislation on their ownership and disposition of our common shares, preferred shares or debentures.

We may sell the securities from time to time in one or more transactions, including block transactions and transactions on the NYSE or on a delayed or continuous basis, in each case, through:

The securities may be sold at a fixed price or prices, which may be changed, or at market prices prevailing at the time of sale, at prices relating to the prevailing market prices or at negotiated prices. The consideration may be cash or another form negotiated by the parties. Agents, underwriters or broker-dealers may be paid compensation for offering and selling the securities. That compensation may be in the form of discounts, concessions or commissions to be received from us or from the purchasers of the securities.

For each offering of common shares, preferred shares, depositary shares, subscriptions rights, warrants or debt securities, the prospectus supplement or other offering materials will describe the specific plan, including:

If we use underwriters for a sale of securities, the underwriters may offer and sell the securities at a fixed price or prices, which may be changed, or from time to time at market prices prevailing at the time of sale, at prices related to such prevailing market prices, at negotiated prices or under delayed delivery contracts or other contractual commitments. We also may, from time to time, authorize underwriters acting as agents to offer and sell the securities upon the terms and conditions set forth in any prospectus supplement. Underwriters may sell the securities to or through dealers, and such dealers may receive compensation in the form of discounts, concessions or commissions (which may be changed from time to time) from the underwriters and/or from the purchasers for whom they may act as agent.

Offers to purchase the securities may be solicited by agents designated by us from time to time. Any such agent involved in the offer or sale of the securities will be named, and any commissions payable by the Company to such agent will be set forth in the prospectus supplement. Unless otherwise indicated in the prospectus supplement, any such agent will be acting on a best efforts basis for the period of its appointment. Any such agent may be deemed to be an underwriter, as that term is defined in the Securities Act, of the securities so offered and sold.

We may from time to time engage a firm to act as our agent for one or more offerings of our securities. We sometimes refer to this agent as our "offering agent." If we reach agreement with an offering agent with respect to a specific offering, including the number of securities and any minimum price below which sales may not be made, then the offering agent will try to sell such securities on the agreed terms. The offering agent could make sales in privately negotiated transactions and/or any other method permitted by law, including sales deemed to be an "at-the-market" offering as defined in Rule 415 promulgated under the Securities Act, including sales made directly on the NYSE, or sales made to or through a market maker other than on an exchange. The offering agent will be deemed to be an "underwriter" within the meaning of the Securities Act with respect to any sales effected through an "at-the-market" offering.

If an underwriter or underwriters are utilized in the sale of securities, we will execute an underwriting agreement with such underwriter or underwriters at the time an agreement for such sale is reached, and the names of the specific managing underwriter or underwriters, as well as any other underwriters, and the terms of the transactions, including compensation of the underwriters and dealers, if any, will be set forth in the prospectus supplement, which will be used by the underwriters to resell the securities.

If a dealer is utilized in the sale of the securities, we will sell such securities to the dealer, as principal. The dealer may then resell such securities to the public at varying prices to be determined by such dealer at the time of resale. The name of the dealer and the terms of the transactions will be set forth in the prospectus supplement relating thereto.

Offers to purchase the securities may be solicited directly by us and sales thereof may be made by us directly to institutional investors or others. The terms of any such sales, including the terms of any bidding or auction prices, if utilized, will be described in the prospectus supplement relating thereto.

Some or all of the securities that we offer through this prospectus may be new issues of securities with no established trading market. Any underwriters to whom we sell securities for public offering and sale may make a market in those securities, but they will not be obligated to and they may discontinue any market making at any time without notice. Accordingly, we cannot assure you of the liquidity of, or continued trading markets for, any securities offered pursuant to this prospectus. If we use dealers in the sale, we will sell securities to those dealers as principals. The dealers may then resell the securities to the public at any market price or other prices to be determined by the dealers at the time of resale. If we use agents in the sale, unless we inform you otherwise in the prospectus supplement or other applicable offering materials they will use their reasonable best efforts to solicit purchasers for the period of their appointment. If we sell directly, no underwriters or agents would be involved. In the prospectus supplement or other applicable offering materials, we will name any agent involved in the offer or sale of the offered securities, and we will describe any commissions payable to the agent. We are not making an offer of securities in any state that does not permit such an offer.

If indicated in the applicable prospectus supplement, we may authorize underwriters or other persons acting as our agents to solicit offers by institutions or other suitable purchasers to purchase the securities from us at the public offering price set forth in the prospectus supplement, pursuant to delayed delivery contracts providing for payment and delivery on the date or dates stated in the prospectus supplement. These purchasers may include, among others, commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutions, but will in all cases be subject to our approval. Delayed delivery contracts will be subject to the condition that the purchase of the securities covered by the delayed delivery contracts will not at the time of delivery be prohibited under the laws of any jurisdiction in the United States to which the purchaser is subject. The underwriters and agents will not have any responsibility with respect to the validity or performance of these contracts.

To facilitate the offering of the securities, certain persons participating in the offering may engage in transactions that stabilize, maintain, or otherwise affect the price of the securities. This may include over-allotments or short sales of the securities, which involves the sale by persons participating in the offering of more securities than we sold to them. In these circumstances, these persons would cover the over-allotments or short positions by making purchases in the open market or by exercising their over-allotment option. In addition, these persons may stabilize or maintain the price of the securities by bidding for or purchasing securities in the open market or by imposing penalty bids, whereby selling concessions allowed to dealers participating in the offering may be reclaimed if securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. These transactions may be discontinued at any time.

Underwriters, dealers and agents participating in the distribution of the securities may be deemed to be underwriters, and any discounts and commissions received by them from us or from purchasers of the securities and any profit realized by them on resale of the securities may be deemed to be underwriting discounts and commissions under the Securities Act. If such dealers or agents were deemed to be underwriters, they may be subject to statutory liabilities under the Securities Act. Underwriters, dealers and agents may be entitled, under agreements entered into with us, to indemnification against and contribution toward certain civil liabilities, including liabilities under the Securities Act.

In the ordinary course of business, we may engage in transactions with underwriters, dealers, agents and their affiliates and they may perform services for us.

Unless otherwise set forth in a prospectus supplement, the validity of the securities offered will be passed upon for us by Pepper Hamilton LLP.

The consolidated financial statements and financial statement schedule of CubeSmart, L.P. (formerly U-Store-It, L.P.) as of December 31, 2010 and 2009 and for each of the years in the three-year period ended December 31, 2010 have been incorporated by reference herein in reliance upon the report of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

	Per Share	Total

Initial price to public	$	$
Underwriting discounts and commissions	$	$
Proceeds, before expenses, to CubeSmart	$	$


PROSPECTUS SUPPLEMENT
About This Prospectus Supplement		S-ii
Forward-Looking Statements		S-ii
Summary		S-1
Risk Factors		S-7
Use of Proceeds		S-11
Capitalization		S-12
The Storage Deluxe Acquisition		S-13
Underwriting		S-16
Legal Matters		S-22
Experts		S-22
Incorporation of Certain Information By Reference		S-22
Where You Can Find More Information		S-23
PROSPECTUS
About This Prospectus		1
Where You Can Find More Information		1
Incorporation Of Certain Information By Reference		2
Forward-Looking Statements		4
CubeSmart And The Operating Partnership		5
Risk Factors		6
Use Of Proceeds		6
Ratio Of Earnings To Fixed Charges And Ratio Of Earnings To Combined Fixed Charges And Preference Dividends		7
Description Of CubeSmart's Capital Shares		8
Description Of Depositary Shares		16
Description Of Subscription Rights		19
Description Of Warrants		20
Description Of The Debt Securities		22
Material Federal Income Tax Considerations		38
Plan Of Distribution		68
Legal Matters		70
Experts		70

		Total

	Per Share	Without Option	With Option
Public Offering Price	$	$	$
Underwriting Discounts and Commissions	$	$	$
Proceeds to Us, Before Expenses	$	$	$

			For the years ended December 31,

	For the six months ended June 30, 2011		For the years ended December 31,
	For the six months ended June 30, 2011		2010		2009		2008		2007		2006
Ratio of earnings to fixed charges		0.95		0.74		0.58		0.52		0.52		0.60

			For the years ended December 31,

	For the six months ended June 30, 2011		For the years ended December 31,
	For the six months ended June 30, 2011		2010		2009		2008		2007		2006
Ratio of earnings to combined fixed charges and preference dividends		0.95		0.74		0.58		0.52		0.52		0.60