| Code | Name | Region |
|---|---|---|
| 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 |
| USSBA | Santa Barbara | CA |
| USSCZ | Santa Clara | CA |
| USTCM | Santa Clara | NM |
| USSKR | Santa Clara | UT |
| USSAM | Santa Clarita | CA |
| USSC6 | Santa Claus | IN |
| USSRU | Santa Cruz | CA |
| USSKY | Sandusky, Erie | OH |
| USSWH | Sandwich | IL |
| USSWC | Sandwich | MA |
| USSJD | Sandy | OR |
| USSJE | Sandy | UT |
| USSY3 | Sandy Creek | NY |
| USYHO | Sandy Hook | CT |
| USSO8 | Sandy Hook | MS |
| USAYL | Sandy Lake | PA |
| USSYP | Sandy Point | ME |
| USIW9 | Sandy Ridge | NC |
| USKSR | Sandy River | AK |
| USS3R | Sandy Run | SC |