| Code | Name | Region |
|---|---|---|
| USS4F | Florence | KS |
| USFTP | Flatonia | TX |
| USFLF | Flatrock | MI |
| USFXM | Flaxman Island | AK |
| USFWP | Fleetwood | PA |
| USFMZ | Fleischmanns | NY |
| USFEG | Fleming | GA |
| US3FL | Fleming | NY |
| USZXH | Fleming | OH |
| USFI7 | Fleming Island | FL |
| USFL5 | Fleming Island | FL |
| USFMB | Flemingsburg | KY |
| USG3N | Flemington | GA |
| USFLE | Flemington | NJ |
| USFFZ | Flemington | WV |
| USFHE | Fletcher | NC |
| USYFH | Fletcher | OH |
| USJFT | Fletcher | OK |
| USFNT | Flint | MI |
| USFXI | Flint | TX |
| USFH5 | Flint Hill | VA |
| USFZW | Fitzwilliam | NH |
| USFYC | Five Corners | WA |
| USFIV | Five Finger | AK |
| USFMC | Five Mile | AK |
| USFIP | Five Points | CA |
| USFGL | Flagler | CO |
| USFBF | Flagler Beach | FL |
| USFLG | Flagstaff | AZ |
| USFTO | Flagtown | NJ |
| USFG7 | Flanagan | IL |
| USFDZ | Flanders | NJ |
| USFDQ | Flanders | NY |
| USYFD | Flandreau | SD |
| USFLT | Flat | AK |
| USUJB | Flat River | MO |
| USLTK | Flat Rock | IL |
| USFR4 | Flat Rock | IN |
| USF3K | Flat Rock | MI |
| USLTR | Flat Rock | NC |
| USFLC | Flat Rock | OH |
| USIRH | Firth | NE |
| USF3S | Fischer | TX |
| USIPF | Fish Camp | CA |
| USFHR | Fisher | IL |
| USFZR | Fisher | WA |
| USZFI | Fisher Island, Miami | FL |
| USFSH | Fishers | IN |
| USOQQ | Fishers | NY |
| USFID | Fishers Island | NY |