FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 Date of Report (Date of earliest event reported): October 28, 2025 BAIN CAPITAL SPECIALTY FINANCE, INC. (Exact name of Registrant as Specified in Its Charter) Delaware 814-01175 81-2878769 (State or Other Jurisdiction of Incorporation) 200 Clarendon Street 37th Floor Boston, Massachusetts 02116 (Address of Principal Executive Offices) (Zip Cod ...