| Code | Name | Region |
|---|---|---|
| USSQI | Sterling-rockfalls Apt | IL |
| USSEX | Sterlington | LA |
| UST67 | Sterrett | AL |
| US8TE | Stetson | ME |
| US9SE | Steuben | ME |
| USUYJ | Steubenville | OH |
| USSS7 | Stevens | PA |
| USSTE | Stevens Point | WI |
| USSVS | Stevens Village | AK |
| USSBS | Steamboat Springs | CO |
| USWBB | Stebbins | AK |
| USYDM | Stedman | NC |
| USS5M | Steedman | MO |
| USSXI | Steele | AL |
| USQTL | Steele | MO |
| USNDZ | Steele | ND |
| USVTS | Steeleville | IL |
| USQQX | Steelton | PA |
| USQTV | Steelville | MO |
| USSGQ | Steger | IL |
| USSIC | Steilacoom | WA |
| USTST | Stennis Space Center | MS |
| USZSP | Stephen | MN |
| US4ST | Stephens | VA |
| USEPS | Stephenson | MI |
| USTEP | Stephentown | NY |
| USSEP | Stephenville | TX |
| USSIG | Sterling | AK |
| USSTK | Sterling | CO |
| US5ST | Star City | AR |
| US9SB | Starbuck | MN |
| USXMU | Starke | FL |
| US7SB | Starksboro | VT |
| USSXK | Starkville | MS |
| USRL5 | Starlight | IN |
| USXAR | Starr | SC |
| USXMT | Startex | SC |
| USSU2 | Startup | WA |
| USSCE | State College | PA |
| USTTI | Stateline | NV |
| USUYU | Staten Island | NY |
| USTBR | Statesboro | GA |
| USSVH | Statesville | NC |
| USZIQ | Statesville | VA |
| USST3 | Statham | GA |
| USUNT | Staunton | IL |
| USSHD | Staunton | VA |
| USSAY | Stayton | OR |
| USWSB | Steamboat Bay | AK |
| USNZK | Stanton | IA |