| Code | Name | Region |
|---|---|---|
| USN3F | Nine Mile Falls | WA |
| USUOU | Newtown | MO |
| USNWX | Newtown | OH |
| USNTW | Newtown | PA |
| USNTQ | Newtown Square | PA |
| USZNE | Newville | PA |
| USNZP | Nezperce | ID |
| USNGW | Niagara | WI |
| USIAG | Niagara Falls | NY |
| USNZU | Niangua | MO |
| USNII | Niantic | CT |
| USNIE | Niblack | AK |
| USQNX | Nibley | UT |
| USNC8 | Nicasio | CA |
| USNCQ | Nice | CA |
| USNT3 | Nicetown | PA |
| USNIV | Niceville | FL |
| USNKV | Nichen Cove | AK |
| USNCK | Nicholasville | KY |
| USICH | Nicholls | GA |
| USSN9 | Nichols | NY |
| USNMQ | Newton | IL |
| USEWK | Newton | KS |
| USNTN | Newton | MA |
| USNTM | Newton | MS |
| USOXP | Newton | NC |
| USNWU | Newton | NH |
| USNWN | Newton | NJ |
| USNXW | Newton | TX |
| USQKW | Newton | WI |
| USN2C | Newton Centre | MA |
| USNFS | Newton Falls | NY |
| USZNF | Newton Falls | OH |
| USNGV | Newton Grove | NC |
| USTGX | Newton Highlands | MA |
| USNFM | Newton Upper Falls | MA |
| USNN4 | Newtonville | IN |
| USNNF | Newtonville | MA |
| USNN5 | Newtonville | NY |
| USNTC | Newtown | CT |
| USNXE | Newtown | IN |
| USNWH | Newport | NH |
| USP5W | Newport | OH |
| USNPO | Newport | OR |
| USNPT | Newport | RI |
| USNPR | Newport | TN |
| USVAP | Newport | VA |
| USEFK | Newport | VT |
| USNP6 | Newport | WA |
| USJNP | Newport Beach | CA |