EX-5.1

Exhibit 5.1

PILLSBURY WINTHROP SHAW PITTMAN LLP

1200 Seventeenth Street, NW, Washington, DC 20036

January 3 2022

Federal Realty Investment Trust

909 Rose Avenue, Suite 200

North Bethesda, Maryland 20852

Ladies and Gentlemen:

We have acted as counsel to Federal Realty Investment Trust, a Maryland real estate investment trust formerly known as FRT Holdco REIT before January 1, 2022 (the “Company”), in connection with its filing of Post-Effective Amendment No. 1 (the “Post Effective Amendments”) to the Registration Statements on Form S-8 filed with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Act”), by Federal Realty Interim Real Estate Investment Trust, a Maryland real estate investment trust formerly known as Federal Realty Investment Trust before January 1, 2022 (the “Predecessor”) on June 22, 2020 (Registration No. 333-239351) and November 1, 2007 (Registration No. 333-147081) (collectively, the “Registration Statements”). The Company is filing the Post-Effective Amendments to adopt the Registration Statements pursuant to Rule 414(d) under the Act as the successor issuer to the Predecessor. The Registration Statements, as amended by the Post-Effective Amendments, relate to the offering of common shares of beneficial interest, par value $.01 per share (the “Common Shares”), of the Company that may be offered from time to time pursuant to the Company’s 2020 Performance Incentive Plan or the Company’s 2007 Employee Share Purchase Plan (collectively, the “Plans”).

For purposes of giving the opinions hereinafter set forth, our examination of documents has been limited to examination of copies of the following (each, a “Document,” and collectively, the “Documents”):

(i)

the declaration of trust of the Company, as amended as of the date hereof;

(ii)

the bylaws of the Company, as amended as of the date hereof;

(iii)

the Registration Statements and the Post-Effective Amendments;

(iv)

resolutions of the Board of Trustees of the Company adopted on December 2, 2021 in the form certified to us by an officer of the Company on the date hereof; and

(ix)

a certificate of an officer of the Company dated as of the date hereof.

Based upon the foregoing and subject to the assumptions, qualifications, limitations, and exceptions set forth below, we are of the opinion that the Common Shares have been duly authorized, and the Common Shares, when issued and delivered by the Company and, as applicable paid for, in the manner described in the Registration Statements and the Plans and in accordance with the resolutions adopted by the Board of Trustees of the Company, will be validly issued, fully paid and nonassessable.

For purposes of this opinion, we have not reviewed any documents other than the Documents. In particular, we have not reviewed any document (other than the Documents) that is referred to in or incorporated by reference into any Document reviewed by us. We have assumed that no provision exists in any document that we have not reviewed that is inconsistent with the opinions stated herein.

In connection with this opinion, we have considered such matters of law and fact as we, in our professional judgment, have deemed necessary or appropriate to render the opinions contained herein. In rendering this opinion letter, we have assumed without independent investigation: (i) the completeness of all Documents; (ii) the genuineness of all signatures; (iii) the legal capacity of all individuals who have executed any of the Documents; (iv) the authenticity of all Documents submitted to us as originals; (v) the conformity to the original documents of all Documents submitted to us as certified, photostatic, reproduced, facsimile or conformed copies of valid existing agreements; (vi) the authenticity of all such latter Documents; and (vii) that the statements regarding matters of fact