| Code | Name | Region |
|---|---|---|
| USRGU | Rogue River | OR |
| USRFH | Rohnert Park | CA |
| USOLK | Roland | OK |
| USRVF | Rolesville | NC |
| US3IX | Roll | AZ |
| USKWE | Rockwell | NC |
| USRY3 | Rockwell City | IA |
| USKOO | Rockwood | IL |
| USR8W | Rockwood | ME |
| USRW2 | Rockwood | MI |
| USRQO | Rockwood | OR |
| USRWU | Rockwood | PA |
| USRKW | Rockwood | TN |
| USRYF | Rocky Face | GA |
| USRKF | Rocky Ford | CO |
| USROK | Rocky Hill | CT |
| USRWI | Rocky Mount | NC |
| USROV | Rocky Mount | VA |
| USRCP | Rocky Point | NC |
| USRKY | Rocky River | OH |
| USDTK | Rodanthe | NC |
| USRD4 | Rodeo | CA |
| USRQE | Rodeo | NM |
| USREF | Roderfield | WV |
| USR9E | Roe | AR |
| USRQP | Rockport | IN |
| USJRT | Rockport | MA |
| USRP3 | Rockport | ME |
| USRC4 | Rockport | MO |
| USRKO | Rockport | NJ |
| USRKP | Rockport | TX |
| USRPR | Rockport | WA |
| USKOB | Rockport | WV |
| USRS6 | Rocksprings | TX |
| USRKT | Rockton | IL |
| USOAL | Rockvale | TN |
| USOCV | Rockville | CT |
| USXXN | Rockville | IN |
| USRKV | Rockville | MD |
| USR79 | Rockville | MN |
| USRK7 | Rockville | RI |
| USR2V | Rockville | VA |
| USQRC | Rockville Centre | NY |
| USR7P | Rockville Township | IL |
| USXLI | Rockwall | TX |
| USZFE | Rockford | AL |
| US7RO | Rockford | IA |
| USRFD | Rockford | IL |
| USRCF | Rockford | MI |
| USKOD | Rockford | MN |