| Code | Name | Region |
|---|---|---|
| USREC | Rose City | MI |
| USQOI | Rose City | TX |
| US7RH | Rose Hill | KS |
| USRZH | Rose Hill | NC |
| USROX | Roseau | MN |
| USRSB | Roseboro | NC |
| USRBZ | Rosebud | MO |
| USIUD | Rosebud | TX |
| USRBG | Roseburg | OR |
| USB8H | Rosebush | MI |
| USRDA | Rosedale | AR |
| USRN9 | Rosedale | IN |
| USZED | Rosedale | KS |
| USRSA | Rosedale | MD |
| USRAE | Rosedale | MS |
| USROU | Romulus | MI |
| USRUZ | Romulus | NY |
| USRNW | Ronan | MT |
| USROT | Ronceverte | WV |
| USQDA | Ronda | NC |
| USRKK | Ronkonkoma | NY |
| USROJ | Ronks | PA |
| USRO3 | Roodhouse | IL |
| USRPV | Roopville | GA |
| USROL | Roosevelt | UT |
| USRLT | Roosevelt | WA |
| USRVT | Rooseveltown | NY |
| USROO | Roosville | MT |
| USR34 | Rootstown | OH |
| USNCW | Roper | NC |
| USRVP | Ropesville | TX |
| USRZA | Rosalia | WA |
| USRSZ | Rosamond | CA |
| USRK2 | Rosanky | TX |
| USRSJ | Rosario | WA |
| USRK3 | Rolla | KS |
| USRLA | Rolla | MO |
| USRQL | Rolla | ND |
| USRFY | Rolling Fork | MS |
| US5RH | Rolling Hills | CA |
| USRHJ | Rolling Hills Estates | CA |
| USRLM | Rolling Meadows | IL |
| USRPA | Rolling Prairie | IN |
| USRJS | Rollins | MT |
| USR3O | Rollinsford | NH |
| USFAL | Roma | TX |
| USRMG | Rome | GA |
| USRME | Rome | NY |
| USRQM | Rome | OK |
| USREO | Rome | OR |