On September 9, 2026, Oaktree Specialty Lending Corporation entered into an underwriting agreement to issue $300.0 million aggregate principal amount of 7.000% Notes due 2031. The transaction is being managed by a syndicate of underwriters led by J.P. Morgan Securities LLC, alongside BNP Paribas Securities Corp., ING Financial Markets LLC, RBC Capital Markets LLC, and SMBC Nikko Securities America, Inc.

The closing of the offering is scheduled for September 16, 2026, subject to customary closing conditions. The company expects to receive net proceeds of $296.5 million, which accounts for an underwriting discount of $2.6 million and estimated offering expenses of approximately $0.8 million.

The issuance is being made pursuant to the company’s effective shelf registration statement on Form N-2 (Registration No. 333-292920), as supplemented by a preliminary prospectus supplement dated September 9, 2026, and a final prospectus supplement dated September 9, 2026.