Exhibit 5.1

[__________], 2023

Extra Space Storage Inc.

2795 East Cottonwood Parkway, Suite 300

Salt Lake City, Utah 84121

Re: Registration Statement on Form S-4

Ladies and Gentlemen:

We have served as Maryland counsel to Extra Space Storage Inc., a Maryland corporation (the “Company”), in connection with certain matters of Maryland law relating to the registration and issuance of up to 78,031,736 shares (the “Shares”) of common stock, par value $0.01 per share (the “Common Stock”), of the Company, to be issued pursuant the Agreement and Plan of Merger, dated as of April 2, 2023, as amended on May [__], 2023 and as it may be further amended from time to time (the “Merger Agreement”), by and among the Company, Extra Space Storage LP, Life Storage, Inc. (“Life Storage”), Life Storage LP, Eros Merger Sub, LLC (“Merger Sub”) and Eros OP Merger Sub, LLC (“OP Merger Sub”), pursuant to which Merger Sub, a newly created wholly owned subsidiary of the Company, will merge with and into Life Storage with Life Storage continuing as the surviving entity (the “Merger”), pursuant to which each outstanding share of common stock, par value $0.01 per share, of Life Storage (other than shares of common stock of Life Storage owned by Life Storage, Life Storage LP, the Company, Extra Space Storage LP, Merger Sub, OP Merger Sub or any of their respective wholly owned subsidiaries, which will be cancelled) will be converted into the right to receive 0.895 of a Share. The Shares are covered by the above-referenced Registration Statement, and all amendments thereto (collectively, the “Registration Statement”), filed by the Company with the U.S. Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “1933 Act”).

In connection with our representation of the Company, and as a basis for the opinion hereinafter set forth, we have examined originals, or copies certified or otherwise identified to our satisfaction, of the following documents (hereinafter collectively referred to as the “Documents”):

1.        The Registration Statement, and the joint proxy statement/prospectus included therein, filed with the Commission under the 1933 Act;

2.        The charter of the Company (the “Charter”), certified by the State Department of Assessments and Taxation of Maryland (the “SDAT”);

3.        The Second Amended and Restated Bylaws of the Company, certified as of the date hereof by an officer of the Company;

Extra Space Storage Inc.

[_______], 2023

Page  2

4.        Resolutions (the “Resolutions”) adopted by the Board of Directors of the Company relating to, among other matters, (i) the filing of the Registration Statement, (ii) the registration and issuance of the Shares pursuant to the Merger Agreement and (iii) the approval of the Merger and the other transactions contemplated by the Merger Agreement, certified as of the date hereof by an officer of the Company;

5.        The Merger Agreement;

6.        A certificate of the SDAT as to the good standing of the Company, dated as of a recent date;

7.        A certificate executed by an officer of the Company, dated as of the date hereof; and

8.        Such other documents and matters as we have deemed necessary or appropriate to express the opinion set forth below, subject to the assumptions, limitations and qualifications stated herein.

In expressing the opinion set forth below, we have assumed the following:

1.        Each individual executing any of the Documents, whether on behalf of such individual or another person, is legally competent to do so.

2.        Each individual executing any of the Documents on behalf of a party (other than the Company) is duly authorized to do so.

3.        Each of the parties (other than the Company) executing any of the Documents has duly and validly executed and delivered each of the Documents to which such party is a signatory, and such party’s obligations set forth therein are legal, valid and binding and are enforceable in accordance with all stated terms.

4.        All Documents submitted to us as originals are authentic. The form and content of all Documents submitted to us as unexecuted drafts do not differ in any respect relevant to this opinion from the form and content of such Documents as executed and delivered. All Documents submitted to us as certified or photostatic copies conform to the original documents. All signatures on all Documents are genuine. All public records reviewed or relied upon by us or on our behalf are true and complete. All representations, warranties, statements and information contained in the Documents are true and complete. There has been no oral or written modification of or amendment to any of the Documents, and there has been no waiver of any provision of any of the Documents, by action or omission of the parties or otherwise.

Extra Space Storage Inc.

[_______], 2023

Page  3

5.        The Shares will not be issued or transferred in violation of any restriction or limitation contained in Article VI of the Charter.

6.        Prior to the issuance of any Shares, the stockholders of the Company will approve the issuance of the Shares pursuant to the Merger and in accordance with the Merger Agreement. Upon the issuance of any Shares, the total number of shares of Common Stock issued and outstanding will not exceed the total number of shares of Common Stock that the Company is then authorized to issue under the Charter. We note that, as of the date hereof, there are more than 78,031,736 shares of Common Stock available for issuance under the Charter.

Based upon the foregoing, and subject to the assumptions, limitations and qualifications stated herein, it is our opinion that:

1.        The Company is a corporation duly incorporated and validly existing under and by virtue of the laws of the State of Maryland and is in good standing with the SDAT.

2.        The issuance of the Shares has been duly authorized and, when and to the extent issued and delivered in the Merger pursuant to the Registration Statement, the Resolutions, the Merger Agreement and the Charter, the Shares will be validly issued, fully paid and nonassessable.

The foregoing opinion is limited to the laws of the State of Maryland, and we do not express any opinion herein concerning federal law or the laws of any other state. We express no opinion as to the applicability or effect of federal or state securities laws, including the securities laws of the State of Maryland, or as to federal or state laws regarding fraudulent transfers. To the extent that any matter as to which our opinion is expressed herein would be governed by the laws of any jurisdiction other than the State of Maryland, we do not express any opinion on such matter. The opinion expressed herein is subject to the effect of any judicial decision which may permit the introduction of parol evidence to modify the terms or the interpretation of agreements.

The opinion expressed herein is limited to the matters specifically set forth herein and no other opinion shall be inferred beyond the matters expressly stated. We assume no obligation to supplement this opinion if any applicable law changes after the date hereof or if we become aware of any fact that might change the opinion expressed herein after the date hereof.

Extra Space Storage Inc.

[_______], 2023

Page  4

This opinion is being furnished to you for submission to the Commission as an exhibit to the Registration Statement. We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the use of the name of our firm therein. In giving this consent, we do not admit that we are within the category of persons whose consent is required by Section 7 of the 1933 Act.

Very truly yours