UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 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): June 22, 2023 (June 16, 2023)

Gladstone Capital Corporation

(Exact name of registrant as specified in its charter)

(703) 287-5800

(Registrant’s telephone number, including area code)

(Former name or former address, if changed since last report)

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.  ☐

On June 16, 2023, Gladstone Capital Corporation (the “Company”), through its wholly-owned subsidiary Gladstone Business Loan, LLC, entered into Amendment No. 4 (the “Amendment”) to its Sixth Amended and Restated Credit Agreement with KeyBank National Association (“KeyBank”), as administrative agent, lead arranger and lender, Gladstone Management Corporation, the Company’s Adviser, as servicer, and certain other lenders party thereto (together with the Amendment, the “Credit Facility”).

Under the terms of the Amendment, the Credit Facility was amended to, among other things, extend the revolving period of the Credit Facility to October 30, 2025 and extend the final maturity date of the Credit Facility to two years after the termination of the revolving period. The interest rate margin is 3.00% during the revolving period and 3.50% thereafter, with a SOFR floor of 0.10%. The available borrowing commitments at close are $223.7 million and can be increased up to a maximum of $350.0 million pursuant to the accordion feature. In addition, the amendment provided for changes to certain excess concentration limits including a reduction in the fixed rate loan limit and an update to certain existing terms and covenants including certain change-in-control events. The Credit Facility continues to include customary terms, covenants, events of default and constraints on borrowing availability based on collateral tests for a credit facility of its size and nature.

KeyBank and the other lenders under the Credit Facility, and their respective affiliates, may from time to time receive customary fees and expenses in the performance of investment banking, financial advisory or other services for the Company. The foregoing summary of the Credit Facility is not complete and is qualified in its entirety by reference to the Credit Facility, which is filed as Exhibit 10.1 to this Current Report on Form 8-K and incorporated by reference into this Item 1.01.

The information set forth under Item 1.01 is hereby incorporated by reference into this Item 2.03.

SIGNATURES

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