| Cover | Jan. 10, 2025 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Jan. 10, 2025 |
| Entity File Number | 814-01706 |
| Entity Registrant Name | KKR FS Income Trust Select |
| Entity Central Index Key | 0001975736 |
| Entity Tax Identification Number | 92-3617067 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | 201 Rouse Boulevard |
| Entity Address, City or Town | Philadelphia |
| Entity Address, State or Province | PA |
| Entity Address, Postal Zip Code | 19112 |
| City Area Code | 215 |
| Local Phone Number | 495-1150 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Elected Not To Use the Extended Transition Period | false |
