| Code | Name | Region |
|---|---|---|
| USBLF | Princeton | WV |
| USPJO | Princeton Junction | NJ |
| USQZL | Princeville | HI |
| USPVS | Preston | CT |
| USPSO | Preston | GA |
| USPRN | Preston | IA |
| USPS9 | Preston | ID |
| USPBV | Preston | MD |
| USRET | Preston | MN |
| USPRH | Preston | WA |
| USPB3 | Prestonsburg | KY |
| USRWP | Prewitt | NM |
| USPUC | Price | UT |
| USP43 | Priceville | AL |
| USPYC | Prichard | AL |
| USPT7 | Prichard | WV |
| USRP8 | Priest River | ID |
| USP2R | Primghar | IA |
| USZPM | Primm | NV |
| USIQM | Primm Springs | TN |
| USPFK | Prince Frederick | MD |
| USJPG | Prince George | VA |
| USPA8 | Princess Anne | MD |
| USPRA | Prairieville | LA |
| USPTT | Pratt | KS |
| USPUG | Prattsburg | NY |
| USPV3 | Prattsville | AR |
| US9PV | Prattsville | NY |
| USPRV | Prattville | AL |
| USXPL | Preble | IN |
| USPR9 | Preble | NY |
| USZWZ | Premont | TX |
| USPRW | Prentice | WI |
| USPS8 | Prescott | AR |
| USPRC | Prescott | AZ |
| USRSC | Prescott | OR |
| USPQW | Prescott | WA |
| USPC5 | Prescott | WI |
| USPV4 | Prescott Valley | AZ |
| USPUO | Presho | SD |
| USPRE | Presidio | TX |
| USPQI | Presque Isle | ME |
| USPSS | Presque Isle | MI |
| USPP4 | Powells Point | NC |
| USXKY | Powers Lake | WI |
| USZPW | Powhatan | VA |
| US8PW | Pownal | ME |
| USYPW | Pownal | VT |
| USVPJ | Poy Sippi | WI |
| USPOV | Poynette | WI |