BLACKSTONE MORTGAGE TRUST, INC.

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

(Amendment No. )

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

Check the appropriate box:

BLACKSTONE MORTGAGE TRUST, INC.

(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):

Blackstone Mortgage Trust, Inc. BXMT BXMT_2026_Proxy_Cover_v4.indd 1 4/23/2026 11:18:30 AM

April 29, 2026

Dear Fellow Stockholders:

You are cordially invited to attend the 2026 annual meeting of stockholders of Blackstone Mortgage Trust, Inc., a Maryland corporation, which will be held at 9:00 a.m., Eastern Daylight Time, on Friday, June 26, 2026, in virtual meeting format only. At the annual meeting, stockholders will be asked to:

Details concerning those matters to come before stockholders at the annual meeting are described in the attached notice of annual meeting of stockholders and proxy statement.

Your management and your board of directors unanimously recommend that you vote FOR all nominees for directors, FOR the ratification of the appointment of Deloitte as the company’s independent registered public accounting firm for 2026, and FOR the approval of the advisory resolution relating to the compensation of our named executive officers as disclosed in the accompanying proxy statement.

As in prior years, we will be using the “Notice and Access” method of providing proxy materials to you via the Internet. We believe that this process will provide you with a convenient and environmentally friendly way to access the proxy materials, including our proxy statement and 2025 annual report to stockholders, and authorize a proxy to vote your shares, while allowing us to conserve natural resources and reduce the costs of printing and distributing the proxy materials.

The proxy statement and form of proxy will be distributed or made available on or about April 29, 2026. We will mail to our stockholders a Notice of Internet Availability of Proxy Materials, which we refer to as the Notice and Access Card, containing instructions on how to access our proxy statement and our 2025 annual report to stockholders and authorize a proxy to vote electronically via the Internet or by telephone. The Notice and Access Card also contains instructions as to how you can receive a paper copy of our proxy materials and authorize a proxy to vote by mail.

It is important that your shares be represented at the annual meeting and voted in accordance with your wishes. Whether or not you plan to attend the meeting, we urge you to complete a proxy as promptly as possible — by Internet, telephone or mail — so that your shares will be voted at the annual meeting. This will not limit your right to vote in person or to attend the meeting.

On behalf of the board of directors, I thank you for your continuing support.

Sincerely,

/s/ Timothy S. Johnson

Timothy S. Johnson

Chief Executive Officer and Chair of the Board of Directors

Notice of 2026 Annual Meeting of Stockholders and Proxy Statement

To our Stockholders:

We hereby notify you that Blackstone Mortgage Trust, Inc., a Maryland corporation (the “Company”), is holding its 2026 annual meeting of stockholders (the “annual meeting”), on Friday, June 26, 2026, at 9:00 a.m., Eastern Daylight Time. You can attend the annual meeting online, vote your shares electronically and submit your questions during the annual meeting, by visiting www.virtualshareholdermeeting.com/BXMT2026. You will need to have your 16-digit control number included on your proxy card or the instructions that accompanied your proxy materials in order to join the annual meeting.

At the annual meeting, stockholders will be asked to:

You can vote your shares of class A common stock if the Company’s records show that you were a stockholder of record as of the close of business on April 13, 2026, the record date for the annual meeting.

Stockholders, whether or not they expect to attend the meeting, are requested to authorize a proxy to vote their shares electronically via the Internet, by telephone or by completing and returning the proxy card if you requested paper copies of the Company’s proxy materials. Voting instructions are provided in the Notice of Internet Availability of Proxy Materials, or, if you requested paper copies, the instructions are printed on your proxy card and included in the accompanying proxy statement. Any person giving a proxy has the power to revoke it at any time prior to the meeting and stockholders who attend the meeting and who are eligible to vote may withdraw their proxies and vote in person.

Sincerely,

/s/ Scott Mathias

Scott Mathias

Chief Compliance Officer and Secretary

April 29, 2026