Exhibit 31.2
CERTIFICATION
I, William Goebel, certify that:
| 1. | I have reviewed this Amendment No. 1 to the annual report on Form 10-K of FS Investment Corporation III; and |
| 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: April 24, 2019
| /s/ WILLIAM GOEBEL | |
| William Goebel | |
| Chief Financial Officer |