| Code | Name | Region |
|---|---|---|
| USNXP | Noxapater | MS |
| USNOY | Noyes | MN |
| USNUA | Nucla | CO |
| USNUE | Nuevo | CA |
| USNUI | Nuiqsut | AK |
| USNUL | Nulato | AK |
| USNUP | Nunapitchuk | AK |
| USNXN | Nunda | NY |
| USNZ9 | Nunica | MI |
| USVUN | Nunn | CO |
| USNLL | Nunnelly | TN |
| USORQ | Norwalk | CT |
| USNKJ | Norwalk | IA |
| USXJR | Norwalk | OH |
| USNJO | Norway | IA |
| USN4Y | Norway | ME |
| USNZO | Norway | MI |
| USNOW | Norwell | MA |
| USNOC | Norwich | CT |
| USNW5 | Norwich | KS |
| USOIC | Norwich | NY |
| USNQW | Norwich | VT |
| USOWD | Norwood | MA |
| USYNW | Norwood | MN |
| USNXO | Norwood | NC |
| USNRD | Norwood | NJ |
| USZNO | Norwood | NY |
| USNDY | Norwood | OH |
| USNXL | Norwood | PA |
| USTXQ | Noti | OR |
| USNT7 | Nottingham | MD |
| USNJX | Northstar | CA |
| USNUM | Northumberland | PA |
| USNVL | Northvale | NJ |
| USNTV | Northville | MI |
| USNVR | Northville (riverhead) | NY |
| USORT | Northway | AK |
| USNZD | Northwood | IA |
| USWO6 | Northwood | ND |
| USN5W | Northwood | NH |
| USNW4 | Northwood, Logan | OH |
| USNHW | Northwood, Wood | OH |
| USNT8 | Norton | KS |
| USNNM | Norton | MA |
| USNOG | Norton | VA |
| USNRT | Norton | VT |
| USNTR | Norton Shores | MI |
| USNNU | Norton, Summit | OH |
| USNV2 | Nortonville | KS |
| USOJV | Nortonville | KY |