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OFFICE PROPERTIES INCOME TRUST FOR IMMEDIATE RELEASE Exhibit 99.1 Two Newton Place 255 Washington Street , Suite 300 Newton , Massachusetts 02458 617-219-1440 opireit.com Office Properties Income Trust Announces Second Quarter 2026 Results Newton , MA ( August 5 , 2026 ) : Office Properties Income Trust ( Nasdaq : OPI ) today announced its financial results for the quarter ended June 30 , 2026 , which can be found at the Quarterly Results section of OPI's website at https://www.opireit.com/investors/financial-information/default.aspx . A conference call discussing OPI's second quarter results will be held on Thursday , August 6 , 2026 at 9:00 a.m. Eastern Time . The conference call may be accessed by dialing ( 877 ) 328-1172 or ( 412 ) 317-5418 ( if calling from outside the United States and Canada ) ; a pass code is not required . A replay will be available for one week by dialing ( 855 ) 669-9658 ; the replay pass code is 2878755. A live audio webcast of the conference call will also be available in a listen only mode on OPI's website , at www.opireit.com . The archived webcast will be available for replay on OPI's website after the call . The transcription , recording and retransmission in any way of OPI's second quarter conference call are strictly prohibited without the prior written consent of OPI . About Office Properties Income Trust : OPI is a national REIT focused on owning and leasing office properties to high credit quality tenants in markets throughout the United States . As of June 30 , 2026 , approximately 62 % of OPI's revenues were from investment grade rated tenants . OPI owned 122 properties as of June 30 , 2026 , with approximately 17.1 million square feet located in 29 states and Washington , D.C. OPI is managed by The RMR Group ( Nasdaq : RMR ) , a leading U.S. alternative asset management company with over $ 37 billion in assets under management as of June 30 , 2026 , and 40 years of institutional experience in buying , selling , financing and operating commercial real estate . OPI is headquartered in Newton , MA . For more information , visit opireit.com . Contact : Kevin Barry , Senior Director , Investor Relations ( 617 ) 219-1410 A Maryland Real Estate Investment Trust with transferable shares of beneficial interest listed on the Nasdaq . No shareholder , Trustee or officer is personally liable for any act or obligation of the Trust .