Exhibit 31.1

Certification of Chief Executive Officer

pursuant to Rule 13a-14 under the Exchange Act of 1934, as adopted

pursuant to Section 302 of the Sarbanes-Oxley Act of 2002

I, R. David Spreng, as Chief Executive Officer, certify that:

1. I have reviewed this Amendment No. 1 to the annual report on Form 10-K of Runway Growth Finance Corp.;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

Date: March 27, 2025

/s/ R. David Spreng

R. David Spreng

Chief Executive Officer

(Principal Executive Officer)

Runway Growth Finance Corp.