| Code | Name | Region |
|---|---|---|
| USSFQ | Saraland | AL |
| USSRN | Saranac | MI |
| USSLK | Saranac Lake | NY |
| USZOR | Sarasota | FL |
| USXMQ | Saratoga | CA |
| USSRB | Saratoga | MN |
| USSAA | Saratoga | WY |
| USSGA | Saratoga Springs | NY |
| USS6T | Saratoga Springs | UT |
| USXX5 | Sarcoxie | MO |
| USAII | Sardinia | NY |
| USS2D | Sardinia | OH |
| USSSR | Sardis | MS |
| USAEP | Sarepta | LA |
| USWSF | Sarichef | AK |
| USS4Y | Sarita | TX |
| USSAO | Sarles | ND |
| USTQA | Santa Elena | TX |
| USSAF | Santa Fe | NM |
| USFEZ | Santa Fe | TX |
| USUYR | Santa Fe Springs | CA |
| USSMG | Santa Margarita | CA |
| USSMX | Santa Maria | CA |
| USSMO | Santa Monica | CA |
| USSZP | Santa Paula | CA |
| USSTS | Santa Rosa | CA |
| USAOA | Santa Rosa | NM |
| USZRS | Santa Rosa | TX |
| USJQJ | Santa Rosa Beach | FL |
| USRO2 | Santa Rosa Island | CA |
| USSXT | Santa Teresa | NM |
| USSQA | Santa Ynez | CA |
| USSY9 | Santa Ysabel | CA |
| USIUQ | Santaquin | UT |
| USSXD | Santee | CA |
| USSA6 | Santee | SC |
| USP8P | Santo | TX |
| USSFM | Sanford | ME |
| USFU7 | Sanford | MI |
| USSCF | Sanford | NC |
| USS3F | Sanford | NY |
| USSRK | Sanger | CA |
| USSGJ | Sanger | TX |
| USS9A | Sangerfield | NY |
| US9SV | Sangerville | ME |
| USSBP | Sanibel | FL |
| USNXJ | Santa | ID |
| USSNA | Santa Ana | CA |
| USXZB | Santa Ana Pueblo | NM |
| USNNX | Santa Anna | TX |