| Code | Name | Region |
|---|---|---|
| USPTZ | Pittsfield | PA |
| USPF3 | Pittsfield | VT |
| USPYN | Pinson | AL |
| USPI2 | Pinson | TN |
| USZ4D | Pinto | MD |
| USP9O | Pinto Island | AL |
| USPJM | Pinyon Pines | CA |
| USPI4 | Pioche | NV |
| USPYH | Pioneer | OH |
| USNE4 | Pioneer | TN |
| USPN3 | Pioneer, Amador | CA |
| USPC4 | Piper City | IL |
| USPEV | Pipersville | PA |
| USPZP | Piperton | TN |
| USPPE | Pipestone | MN |
| USPQA | Piqua | OH |
| USPIU | Piru | CA |
| USPIL | Piscataway | NJ |
| USPAG | Pisgah | AL |
| USPGF | Pisgah Forest | NC |
| USPB5 | Pismo Beach | CA |
| USPCF | Pitcairn | PA |
| USP2D | Pineland | SC |
| USPPB | Pinellas Park | FL |
| USP2T | Pinetop | AZ |
| USPTP | Pinetops | NC |
| USPIV | Pineville | AL |
| USPVL | Pineville | AR |
| USP8Y | Pineville | KY |
| USPVE | Pineville | LA |
| USIIU | Pineville | MO |
| USPNV | Pineville | NC |
| USXKO | Pineville | SC |
| USPMC | Pineville | WV |
| USEYF | Piney Flats | TN |
| USPYP | Piney Point | MD |
| USPI5 | Piney River | VA |
| USPQG | Pingree | ID |
| USIEE | Pingree Grove | IL |
| USPQ9 | Pink Hill | NC |
| USZHA | Pinnacle | NC |
| USP2C | Pinole | CA |
| USNLV | Pine Level, Johnston | NC |
| USPIM | Pine Mountain | GA |
| USPM2 | Pine Mountain Valley | GA |
| USQPY | Pine Plains | NY |
| USXPR | Pine Ridge | SD |
| USP4R | Pine Rive | WI |
| USPJR | Pine River | MN |
| USPVA | Pine Valley | CA |