EX-99.906

CERTIFICATION

David Gladstone, Chief Executive Officer, and Michael Malesardi, Chief Financial Officer of Gladstone Alternative Income Fund (the “Registrant”), each certify to the best of his knowledge that:

1. The Registrant’s periodic report on Form N-CSR for the period ended September 30, 2025 (the “Form N-CSR”) fully complies with the requirements of Sections 13(a) or 15(d), as applicable, of the Securities Exchange Act of 1934, as amended; and

2. The information contained in the Form N-CSR fairly presents, in all material respects, the financial condition and results of operations of the Registrant.

Chief Executive Officer |  |  |  | Chief Financial Officer
Gladstone Alternative Income Fund |  |  |  | Gladstone Alternative Income Fund
/s/ David Gladstone |  |  |  | /s/ Michael Malesardi
David Gladstone, Chief Executive Officer |  |  |  | Michael Malesardi, Chief Financial Officer
December 4, 2025 |  |  |  | December 4, 2025

This certification is being furnished to the Commission solely pursuant to 18 U.S.C. § 1350 and is not being filed as part of the Form N-CSR filed with the Commission.

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