| Code | Name | Region |
|---|---|---|
| USCJY | Crosby | TX |
| USCXY | Crosbyton | TX |
| US8CR | Cross | SC |
| USCTY | Cross City | FL |
| USCXG | Cross Junction | VA |
| USXL4 | Cross Lanes | WV |
| US5CP | Cross Plains | IN |
| USUOP | Cross Plains | TN |
| USCXH | Cross Plains | WI |
| USC2S | Cross Roads | TX |
| USCRT | Crossett | AR |
| USCK4 | Crosslake | MN |
| US9CR | Crossnore | NC |
| USXRD | Crossroads | GA |
| USQCR | Crossroads | TX |
| USCR9 | Crossville | AL |
| US7CR | Crossville | IL |
| USCSV | Crossville | TN |
| USCXA | Croswell | MI |
| USCVH | Crothersville | IN |
| USCRI | Crisfield | MD |
| USITD | Crittenden | KY |
| USCQ7 | Crivitz | WI |
| USCRM | Crockett | CA |
| USKHT | Crockett | KY |
| USXOK | Crockett | TX |
| USOFN | Crofton | KY |
| USZCN | Crofton | MD |
| USRFT | Crofton | NE |
| USC8G | Cromberg | CA |
| USZCW | Cromwell | CT |
| USXYX | Cromwell | IN |
| USC8W | Cromwell | KY |
| USCKD | Crooked Creek | AK |
| USCKN | Crookston | MN |
| USOOS | Crooksville | OH |
| US3RP | Cropsey | IL |
| USCW3 | Cropwell | AL |
| USCGM | Crosby | MN |
| USCSY | Crosby | ND |
| USRZN | Crestline | KS |
| USC7R | Crestline | OH |
| USC8T | Creston | CA |
| USCSQ | Creston | IA |
| USOHR | Creston | OH |
| USC3E | Crestone | CO |
| USCEW | Crestview | FL |
| USRHS | Crestview Hills | KY |
| USCWB | Crestwood | IL |
| USCW7 | Crestwood | KY |