UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT Pursuant
to Section 13 or 15(d) of the
Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): December 15, 2025

OFFICE PROPERTIES INCOME TRUST

(Exact Name of Registrant as Specified in Its Charter)

Maryland

(State or Other Jurisdiction of Incorporation)

617-219-1440

(Registrant’s Telephone Number, Including Area Code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities Registered Pursuant to Section 12(b) of the Act:  

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company    ¨

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ¨

In this Current Report on Form 8-K, the terms “OPI,” “the Company,” “we,” “us,” and “our” refer to Office Properties Income Trust.

Item 7.01. Regulation FD Disclosure.

As previously disclosed, on October 30, 2025 (the “Petition Date”), OPI and certain of its subsidiaries (collectively, the “Debtors”) commenced voluntary cases (the “Chapter 11 Cases”) under chapter 11 of title 11 of the United States Code (the “Bankruptcy Code”) in the United States Bankruptcy Court for the Southern District of Texas (the “Bankruptcy Court”). The Chapter 11 Cases are being filed to implement a court-supervised financial restructuring pursuant to the terms described in that certain Restructuring Support Agreement entered into on October 30, 2025 among the Debtors and the other parties thereto. The Debtors’ Chapter 11 Cases are jointly administered under the caption “In re Office Properties Income Trust, et al.”

Schedules of Assets and Liabilities and Statements of Financial Affairs

On December 15, 2025, the Debtors filed their Schedules of Assets and Liabilities and Statements of Financial Affairs (collectively, the "Schedules and Statements") with the Bankruptcy Court. The Schedules and Statements provide detailed information regarding the Company's assets, liabilities, and financial affairs as of the Petition Date, the previous month-end close on September 30, 2025, or as otherwise specified in the Schedules and Statements. The Debtors continue to operate their businesses and manage their properties as debtors-in-possession under the jurisdiction of the Bankruptcy Court and in accordance with the applicable provisions of the Bankruptcy Code and orders of the Bankruptcy Court.

Copies of the Schedules and Statements are available for review and download, free of charge, on the website of the Debtors’ claims, noticing, and solicitation agent at https://restructuring.ra.kroll.com/OPI or through the Bankruptcy Court's website, for a fee, at https://ecf.txsb.uscourts.gov. The information contained on, or that may be accessed through, the websites referenced in this Current Report on Form 8-K in each case is not incorporated by reference into, and is not a part of, this Current Report on Form 8-K.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this current report to be signed on its behalf by the undersigned hereunto duly authorized.

Dated: December 18, 2025