0001655050 2026-07-28 2026-07-28 false 0001655050 8-K 2026-07-28 BAIN CAPITAL SPECIALTY FINANCE, INC. DE 814-01175 81-2878769 200 Clarendon Street 37th Floor Boston MA 02116 (617) 516-2000 N/A false false false false Common Stock, par value $0.001 per share BCSF NYSE false