| Code | Name | Region |
|---|---|---|
| USXYY | Caraway | AR |
| USC8N | Carbon | IN |
| US4CC | Carbon Cliff | IL |
| USZXP | Carbondale | CO |
| USMDH | Carbondale | IL |
| USK7S | Carbondale | KS |
| USC9D | Carbondale | OH |
| USCQD | Carbondale | PA |
| USA5Y | Capay | CA |
| USPB7 | Cape Blanco | OR |
| USCPV | Cape Canaveral | FL |
| USTPC | Cape Carteret | NC |
| USCCJ | Cape Charles | VA |
| USCC2 | Cape Coral | FL |
| USCEL | Cape Elizabeth | ME |
| USCFN | Cape Fear | NC |
| USCGI | Cape Girardeau | MO |
| USCPH | Cape Hatteras | NC |
| USC65 | Cape Henlopen | DE |
| USXPY | Cape Henry | VA |
| USLUR | Cape Lisburne | AK |
| USCGF | Cape May | NJ |
| USZQH | Cape May Court House | NJ |
| USM6C | Cape Neddick | ME |
| USEHM | Cape Newenham | AK |
| USCZP | Cape Pole | AK |
| USCZF | Cape Romanzof | AK |
| USCSA | Cape Sabine | AK |
| UST9N | Canton | NJ |
| USXAN | Canton | NY |
| USCCO | Canton | OH |
| USAJN | Canton | OK |
| USAOJ | Canton | PA |
| USCTK | Canton | SD |
| USTCN | Canton | TX |
| USCQF | Cantonment | FL |
| USQUK | Cantua Creek | CA |
| USUTL | Canutillo | TX |
| US2WV | Canvas | WV |
| USCJU | Canyon | CA |
| USNYO | Canyon | CA |
| USAYO | Canyon | TX |
| USCY3 | Canyon City | TX |
| USAYC | Canyon Country | CA |
| USC5L | Canyon Lake | CA |
| USZHX | Canyon Lake | TX |
| USYLL | Canyonville | OR |
| USXAP | Capac | MI |
| USIBU | Cannelburg | IN |
| USCUU | Cannelton | IN |