BRANDYWINE REALTY TRUST

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐

Check the appropriate box:

Brandywine Realty Trust

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

Notice of Annual Meeting of Shareholders

To our Shareholders:

We cordially invite you to attend the 2024 Annual Meeting of Shareholders of Brandywine Realty Trust, a Maryland real estate investment trust (the “Company”). To enable shareholder participation from any location, the 2024 annual meeting will be held exclusively online. The annual meeting can be accessed via a live webcast atwww.virtualshareholdermeeting.com/BDN2024. The annual meeting has been designed to provide the same rights to participate as you would have at anin-person meeting. You may also submit questions in advance of the annual meeting by visiting www.proxyvote.com. We will respond to as many inquiries at the annual meeting as time allows. Prior to the annual meeting you will be able to authorize a proxy to vote your shares at www.proxyvote.com on the matters submitted for shareholder approval at the annual meeting, and we encourage you to do so.

If you plan to attend the annual meeting, you will need the 16-digit control number included in your Notice of Internet Availability, on your proxy card or on the instructions that accompany your proxy materials. The annual meeting will begin promptly at 10:00 a.m. (Eastern Time). Online check-in will begin at 9:30 a.m. (Eastern Time), and you should allow ample time for the online check-in procedures.

At the annual meeting, shareholders as of the close of business on the record date will be asked to consider and vote upon the following matters, as more fully described in the Proxy Statement:

YOUR VOTE IS IMPORTANT TO US. Whether or not you plan to virtually attend the 2024 annual meeting, please authorize a proxy to vote your shares as soon as possible to ensure that your shares will be represented at the annual meeting.

By Order of the Board of Trustees

Shawn Neuman, Senior Vice President, General Counsel and Secretary

April 4, 2024

2929 Arch Street, Suite 1800 | Philadelphia, Pennsylvania 19104 | (610)325-5600

Proxy Statement for the

Annual Meeting of Shareholders

To be held on May 23, 2024

The Annual Meeting of Shareholders of Brandywine Realty Trust (“Brandywine,” “we,” “us,” “our” or the “Company”) will be held on Thursday, May 23, 2024 at 10:00 a.m., Eastern Time. To enable shareholder participation from any location, the 2024 annual meeting will be held exclusively online. The annual meeting can be accessed via a live webcast atwww.virtualshareholdermeeting.com/BDN2024. The annual meeting has been designed to provide the same rights to participate as you would have at anin-person meeting.

At our annual meeting, we will ask you:

Only holders of record of our common shares of beneficial interest, par value $0.01 per share, as of the close of business on March 26, 2024 are entitled to notice of and to vote at the annual meeting or at any postponement or adjournment of the meeting.

Our Board of Trustees knows of no other business that will be presented for consideration at the annual meeting. If any other matter should be properly presented at the annual meeting or any postponement or adjournment of the annual meeting for action by the shareholders, the persons named in the proxy card will vote the proxy in accordance with their discretion on such matter.

On or about April 4, 2024, we mailed a Notice of Internet Availability of Proxy Materials to shareholders. This proxy statement and the form of proxy are first being furnished to shareholders on or about April 4, 2024.

Important Notice Regarding Internet Availability of Proxy Materials We are pleased to take advantage of the Securities and Exchange Commission rules allowing companies to furnish proxy materials to their shareholders over the Internet. We believe that this e-proxy process will expedite shareholders’ receipt of proxy materials, lower the costs and reduce the environmental impact of our 2024 annual meeting of shareholders. We will send a full set of proxy materials or a “Notice of Internet Availability” of Proxy Materials on or about April 4, 2024 and provide access to our proxy materials over the Internet, beginning on April 4, 2024, for the holders of record and beneficial owners of our common shares as of the close of business on the record date. The Notice of Internet Availability instructs you on how to access and review the Proxy Statement and our annual report, and how to authorize a proxy to vote your shares over the Internet. Instead of receiving paper copies of future annual reports and proxy statements in the mail, you may elect to receive an e-mail that will provide an electronic link to these documents. Choosing to receive your proxy materials online will save us the cost of producing and mailing documents to you. With electronic delivery, we will notify you by e-mail as soon as the annual report and proxy statement are available on the Internet, and you may easily submit your shareholder votes online. If you are a shareholder of record, you may enroll in the electronic delivery service at the time you vote by selecting electronic delivery if you vote on the Internet, or at any time in the future by going directly to www.proxyvote.com, selecting the “request copy” option, and following the enrollment instructions.

Important Notice Regarding the Availability of Proxy Materials

for the Shareholders Meeting to be Held on May 23, 2024

This proxy statement, the form of proxy and our 2023 annual report to

shareholders are available atwww.proxyvote.com.

CAUTIONARY STATEMENTS FOR FORWARD-LOOKING INFORMATION We have made statements in this Proxy Statement that are forward-looking and therefore are subject to risks and uncertainties. All statements in this document other than statements of historical fact are, or could be, “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements may appear throughout this Proxy Statement. Words such as “may,” “will,” “expect,” “intend,” “estimate,” “anticipate,” “believe,” “should,” “forecast,” “project” or “plan” and terms of similar meaning are also generally intended to identify forward-looking statements. However, the absence of these words does not mean that a statement is not forward-looking. We caution that these statements are subject to numerous important risks, uncertainties, assumptions and other factors, some of which are beyond our control, that could cause our actual results to differ materially from those expressed or implied by such forward-looking statements. A detailed discussion of risks related to our business is included in the section entitled “Risk Factors” in our Annual Report on Form 10-K for the 2023 fiscal year filed with the SEC on February 22, 2024, as supplemented by any subsequently filed Quarterly Report on Form 10-Q. Shareholders, potential investors and others should consider these factors in evaluating the forward-looking statements and should not place undue reliance on such statements. The forward-looking statements included in this Proxy Statement are made only as of the date of this document, unless otherwise specified, and, except as required by law, we assume no obligation, and disclaim any obligation, to update such statements to reflect events or circumstances occurring after the date of this Proxy Statement. WEBSITES Website addresses referenced in this proxy statement are provided for convenience only, and the content on the referenced websites does not constitute a part of this proxy statement.

BRANDYWINE REALTY TRUST