August 1, 2017

2017 Summary Prospectus

^► iShares U.S. Preferred Stock ETF | PFF |  NYSE ARCA

Before you invest, you may want to review the Fund’s prospectus, which contains more information about the Fund and its risks. You can find the Fund’s prospectus (including amendments and supplements) and other information about the Fund, including the Fund’s statement of additional information and shareholder report, online at http://us.ishares.com/prospectus. You can also get this information at no cost by calling 1-800-iShares (1-800-474-2737) or by sending an e-mail request to iSharesETFs@blackrock.com, or from your financial professional. The Fund’s prospectus and statement of additional information, both dated August 1, 2017, as amended and supplemented from time to time, are incorporated by reference into (legally made a part of) this Summary Prospectus.

The Securities and Exchange Commission (“SEC”) has not approved or disapproved these securities or passed upon the adequacy of this prospectus. Any representation to the contrary is a criminal offense.

iSHARES^® U.S. PREFERRED STOCK ETF

Ticker: PFF Stock Exchange: NYSE Arca

Investment Objective

The iShares U.S. Preferred Stock ETF (the “Fund”) seeks to track the investment results of an index composed of U.S. preferred stocks.

Fees and Expenses

The following table describes the fees and expenses that you will incur if you own shares of the Fund. The investment advisory agreement between iShares Trust (the “Trust”) and BlackRock Fund Advisors (“BFA”) (the “Investment Advisory Agreement”) provides that BFA will pay all operating expenses of the Fund, except the management fees, interest expenses, taxes, expenses incurred with respect to the acquisition and disposition of portfolio securities and the execution of portfolio transactions, including brokerage commissions, distribution fees or expenses, litigation expenses and any extraordinary expenses.

You may also incur usual and customary brokerage commissions and other charges when buying or selling shares of the Fund, which are not reflected in the Example that follows:

Annual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investments)
Management Fees	Distribution and Service (12b-1) Fees	Other Expenses1	Total Annual Fund Operating Expenses
0.47%	None	0.00%	0.47%

¹ For the most recently completed fiscal year, the amount of Other Expenses rounded to 0.00%.

Example. This Example is intended to help you compare the cost of owning shares of the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then sell all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

1 Year	3 Years	5 Years	10 Years
$48	$151	$263	$591

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Portfolio Turnover. The Fund may pay transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 23% of the average value of its portfolio.

Principal Investment Strategies

The Fund seeks to track the investment results of the S&P U.S. Preferred Stock Index (the “Underlying Index”), which measures the performance of a select group of preferred stocks listed on the New York Stock Exchange (“NYSE”), NYSE Arca, Inc. (“NYSE Arca”), NYSE Amex, NASDAQ Global Select Market, NASDAQ Select Market or NASDAQ Capital Market. The Underlying Index does not seek to directly reflect the performance of the companies issuing the preferred stock. The Underlying Index includes preferred stocks with a market capitalization over $100 million that meet minimum price, liquidity, trading volume, maturity and other requirements determined by S&P Dow Jones Indices LLC (the “Index Provider” or “SPDJI”), a subsidiary of S&P Global, Inc. The Underlying Index excludes certain issues of preferred stock, such as those that are issued by special ventures (e.g., toll roads or dam operators) or structured products and brand name products issued by financial institutions that are packaged securities linked to indices or other stocks.

In general, preferred stock is a class of equity security that pays a specified dividend that must be paid before any dividends can be paid to common stockholders and takes precedence over common stock in the event of a company's liquidation.

Although preferred stocks represent a partial ownership interest in a company, preferred stocks generally do not carry voting rights and have economic characteristics similar to fixed-income securities. Preferred stocks generally are issued with a fixed par value and pay dividends based on a percentage of that par value at a fixed or variable rate. Additionally, preferred stocks often have a liquidation value that generally equals the original purchase price of the preferred stock at the date of issuance. The Underlying Index may include many different categories of preferred stock, such as floating, variable and fixed-rate preferreds, callable preferreds, convertible preferreds, cumulative and non-cumulative preferreds, trust preferreds or various other traditional and hybrid issues of preferred stock.

The Underlying Index may include large-, mid- or small-capitalization companies. As of March 31, 2017, a significant portion of the Underlying Index is represented by securities of financials companies. The components of the Underlying Index, and the degree to which these components represent certain industries, are likely to change over time.

BFA uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued.

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Indexing may eliminate the chance that the Fund will substantially outperform the Underlying Index but also may reduce some of the risks of active management, such as poor security selection. Indexing seeks to achieve lower costs and better after-tax performance by keeping portfolio turnover low in comparison to actively managed investment companies.

BFA uses a representative sampling indexing strategy to manage the Fund. “Representative sampling” is an indexing strategy that involves investing in a representative sample of securities that collectively has an investment profile similar to that of the Underlying Index. The securities selected are expected to have, in the aggregate, investment characteristics (based on factors such as market capitalization and industry weightings), fundamental characteristics (such as return variability and yield) and liquidity measures similar to those of the Underlying Index. The Fund may or may not hold all of the securities in an applicable underlying index.

The Fund generally will invest at least 90% of its assets in the component securities of the Underlying Index and may invest up to 10% of its assets in certain futures, options and swap contracts, cash and cash equivalents, including shares of money market funds advised by BFA or its affiliates, as well as in securities not included in the Underlying Index, but which BFA believes will help the Fund track the Underlying Index. The Fund seeks to track the investment results of the Underlying Index before fees and expenses of the Fund.

The Fund may lend securities representing up to one-third of the

value of the Fund's total assets (including the value of any collateral received).

The Underlying Index is a product of SPDJI, which is independent of the Fund and BFA. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index.

Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. For purposes of this limitation, securities of the U.S. government (including its agencies and instrumentalities) and repurchase agreements collateralized by U.S. government securities are not considered to be issued by members of any industry.

Summary of Principal Risks

As with any investment, you could lose all or part of your investment in the Fund, and the Fund's performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund's net asset value per share (“NAV”), trading price, yield, total return and ability to meet its investment objective.

Asset Class Risk. Securities and other assets in the Underlying Index or in the Fund's portfolio may underperform in comparison to the general financial markets, a particular financial market or other asset classes.

Assets Under Management (AUM) Risk. From time to time, an Authorized Participant (as defined in the Creations

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and Redemptions section of this prospectus (the “Prospectus”)), a third-party investor, the Fund’s adviser or an affiliate of the Fund’s adviser, or a fund may invest in the Fund and hold its investment for a specific period of time in order to facilitate commencement of the Fund’s operations or for the Fund to achieve size or scale. Therecan be no assurance that any such entity would not redeem its investment or that the size of the Fund would be maintained at such levels, which could negatively impact the Fund.

Authorized Participant Concentration Risk. Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that may act as Authorized Participants on an agency basis (i.e., on behalf of other market participants). To the extent that Authorized Participants exit the business or are unable to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able to step forward to create or redeem Creation Units (as defined in the Purchase and Sale of Fund Shares section of the Prospectus), Fund shares may be more likely to trade at a premium or discount to NAV and possibly face trading halts and/or delisting.

Concentration Risk. The Fund may be susceptible to an increased risk of loss, including losses due to adverse events that affect the Fund’s investments more than the market as a whole, to the extent that the Fund's investments are concentrated in the securities of a particular issuer or issuers, country, region, market, industry, group of industries, sector or asset class.

Cyber Security Risk. Failures or breaches of the electronic systems of the Fund, the Fund's adviser, distributor, and other service providers, market makers, Authorized Participants or the issuers of securities in which the Fund invests have the ability to cause disruptions and negatively impact the Fund’s business operations, potentially resulting in financial losses to the Fund and its shareholders. While the Fund has established business continuity plans and risk management systems seeking to address system breaches or failures, there are inherent limitations in such plans and systems. Furthermore, the Fund cannot control the cyber security plans and systems of the Fund’s service providers, the Index Provider, market makers, Authorized Participants or issuers of securities in which the Fund invests.

Dividend Risk. There is no guarantee that issuers of the stocks held by the Fund will declare dividends in the future or that, if declared, they will either remain at current levels or increase over time.

Equity Securities Risk. Equity securities are subject to changes in value, and their values may be more volatile than those of other asset classes. The Underlying Index is comprised of preferred stocks, holders of which generally are subject to more risks than debt securities because preferred stockholders’ claims are subordinated to holders of debt securities upon the bankruptcy of the issuer.

Financials Sector Risk. Performance of companies in the financials sector may be adversely impacted by many factors, including, among others, changes in government regulations, economic

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conditions, and interest rates, credit rating downgrades, and decreased liquidity in credit markets. The impact of more stringent capital requirements and recent or future regulation of any individual financial company or of the financials sector as a whole cannot be predicted. In recent years, cyber attacks and technology malfunctions and failures have become increasingly frequent in this sector and have caused significant losses to companies in this sector, which may negatively impact the Fund.

Fixed-to-Floating Rate Securities Risk. The Fund invests in fixed-to-floating rate preferred securities, which are securities that have an initial term with a fixed dividend rate and following this initial term bear a floating dividend rate. Securities which include a floating or variable interest rate component can be less sensitive to interest rate changes than securities with fixed interest rates, but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Although floating rate preferred securities can be less sensitive to interest rate risk than fixed-rate preferred securities, they are subject to the risks applicable to preferred securities more generally.

Hybrid Securities Risk. Hybrid securities are subject to the risks of equity securities and risks of debt securities. The claims of holders of hybrid securities of an issuer are generally subordinated to those of holders of traditional debt securities in bankruptcy, and thus hybrid securities may be more volatile and subject to greater risk than traditional debt securities, and may in certain circumstances even be more volatile than traditional equity securities. At the same time, hybrid securities may not

fully participate in gains of their issuer and thus potential returns of such securities are generally more limited than traditional equity securities, which would participate in such gains.

Index-Related Risk. There is no guarantee that the Fund will achieve a high degree of correlation to the Underlying Index and therefore achieve its investment objective. Market disruptions and regulatory restrictions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track the Underlying Index. Errors in index data, index computations and/or the construction of the Underlying Index in accordance with its methodology may occur from time to time and may not be identified and corrected by the Index Provider for a period of time or at all, which may have an adverse impact on the Fund and its shareholders.

Interest Rate Risk. An increase in interest rates may cause the value of securities held by the Fund to decline, may lead to heightened volatility in the fixed-income markets and may adversely affect the liquidity of certain fixed-income investments. The historically low interest rate environment increases the risks associated with rising interest rates.

Issuer Risk. The performance of the Fund depends on the performance of individual securities to which the Fund has exposure. Changes in the financial condition or credit rating of an issuer of those securities may cause the value of the securities to decline.

Large-Capitalization Companies Risk. Large-capitalization companies may be less able than smaller capitalization companies to adapt to changing market conditions. Large-capitalization

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companies may be more mature and subject to more limited growth potential compared with smaller capitalization companies. During different market cycles, the performance of large-capitalization companies has trailed the overall performance of the broader securities markets.

Management Risk. As the Fund may not fully replicate the Underlying Index, it is subject to the risk that BFA's investment strategy may not produce the intended results.

Market Risk. The Fund could lose money over short periods due to short-term market movements and over longer periods during more prolonged market downturns.

Market Trading Risk. The Fund faces numerous market trading risks, including the potential lack of an active market for Fund shares, losses from trading in secondary markets, periods of high volatility and disruptions in the creation/redemption process. ANY OF THESE FACTORS, AMONG OTHERS, MAY LEAD TO THE FUND'S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV.

Operational Risk. The Fund is exposed to operational risks arising from a number of factors, including, but not limited to, human error, processing and communication errors, errors of the Fund’s service providers, counterparties or other third-parties, failed or inadequate processes and technology or systems failures. The Fund and BFA seek to reduce these operational risks through controls and procedures. However, these measures do not address every possible risk and may be inadequate to address these risks.

Passive Investment Risk. The Fund is not actively managed, and BFA generally does not attempt to take defensive positions under any market conditions, including declining markets.

Preferred Stock Risk. Preferred stock is subject to many of the risks associated with debt securities, including interest rate risk. In addition, preferred stocks may not pay dividends, an issuer may suspend payment of dividends on U.S. preferred stock at any time, and in certain situations an issuer may call or redeem its preferred stock or convert it to common stock. To the extent that the Fund invests a substantial portion of its assets in convertible preferred stocks, declining common stock values may also cause the value of the Fund’s investments to decline.

Risk of Investing in the United States. The Fund has significant exposure to U.S. issuers. Certain changes in the U.S. economy, such as when the U.S. economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.

Securities Lending Risk. The Fund may engage in securities lending. Securities lending involves the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. These events could also trigger adverse tax consequences for the Fund.

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Tracking Error Risk. Tracking error is the divergence of a fund’s performance from that of the applicable underlying index. Tracking error may occur because of differences between the securities and other instruments held in a fund’s portfolio and those included in the applicable underlying index, pricing differences (including, as applicable, differences between a security’s price at the local market close and the fund's valuation of a security at the time of calculation of the fund's NAV), differences in transaction costs, the fund’s holding of uninvested cash,

differences in timing of the accrual of or the valuation of dividends or interest, tax gains or losses, changes to the applicable underlying index or the costs to the fund of complying with various new or existing regulatory requirements. This risk may be heightened during times of increased market volatility or other unusual market conditions. Tracking error also may result because a fund incurs fees and expenses, while the applicable underlying index does not.

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Performance Information

The bar chart and table that follow show how the Fund has performed on a calendar year basis and provide an indication of the risks of investing in the Fund. Both assume that all dividends and distributions have been reinvested in the Fund. Past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Supplemental information about the Fund’s performance is shown under the heading Total Return Information in the Supplemental Information section of the Prospectus.

Year-by-Year Returns¹ (Years Ended December 31)

¹ The Fund’s year-to-date return as of June 30, 2017 was 7.75%.

The best calendar quarter return during the periods shown above was 45.25% in the 2nd quarter of 2009; the worst was -29.22% in the 3rd quarter of 2008.

Updated performance information is available at www.iShares.com or by calling 1-800-iShares (1-800-474-2737) (toll free).

Average Annual Total Returns

(for the periods ended December 31, 2016)

	One Year	Five Years	Since Fund Inception
(Inception Date: 3/26/2007)
Return Before Taxes	1.26%	7.15%	3.93%
Return After Taxes on Distributions2	-0.43%	5.30%	1.97%
Return After Taxes on Distributions and Sale of Fund Shares2	1.49%	5.16%	2.49%
S&P U.S. Preferred Stock Index (Index returns do not reflect deductions for fees, expenses, or taxes)	1.94%	7.75%	4.40%

² After-tax returns in the table above are calculated using the historical highest individual U.S. federal marginal income tax rates and do not reflect the impact of state or local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown are not relevant to tax-exempt investors or investors who hold shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). Fund returns after taxes on distributions and sales of Fund shares are calculated assuming that an investor has sufficient capital gains of the same character from other investments to offset any capital losses from the sale of Fund shares. As a result, Fund returns after taxes on distributions and sales of Fund shares may exceed Fund returns before taxes and/or returns after taxes on distributions.

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Management

Investment Adviser. BlackRock Fund Advisors.

Portfolio Managers. Diane Hsiung, Jennifer Hsui, Alan Mason and Greg Savage (the “Portfolio Managers”) are primarily responsible for the day-to-day management of the Fund. Each Portfolio Manager supervises a portfolio management team. Ms. Hsiung, Ms. Hsui, Mr. Mason and Mr. Savage have been Portfolio Managers of the Fund since 2008, 2012, 2016 and 2008, respectively.

Purchase and Sale of Fund Shares

The Fund is an ETF. Individual shares of the Fund are listed on a national securities exchange. Most investors will buy and sell shares of the Fund through a broker-dealer. The price of Fund shares is based on market price, and because ETF shares trade at market prices rather than at NAV, shares may trade at a price greater than NAV (a premium) or less than NAV (a discount). The Fund will only issue or redeem shares that have been aggregated into blocks of 50,000 shares or multiples thereof (“Creation Units”) to Authorized Participants who have entered into agreements with the Fund's distributor. The Fund generally will issue or redeem Creation Units in return for a designated portfolio of securities (and an amount of cash) that the Fund specifies each day.

Tax Information

The Fund intends to make distributions that may be taxable to you as ordinary income or capital gains, unless you are investing through a tax-deferred arrangement such as a 401(k) plan or an IRA, in which case, your distributions generally will be taxed when withdrawn.

Payments to Broker-Dealers and other Financial Intermediaries

If you purchase shares of the Fund through a broker-dealer or other financial intermediary (such as a bank), BFA or other related companies may pay the intermediary for marketing activities and presentations, educational training programs, conferences, the development of technology platforms and reporting systems or other services related to the sale or promotion of the Fund. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

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For more information visit www.iShares.com or call 1-800-474-2737

IS-SP-PFF-0817

Investment Company Act file No.: 811-09729