| Code | Name | Region |
|---|---|---|
| USUEB | Lunenburg | VT |
| USLP2 | Lupton | MI |
| USLP3 | Lupton | NC |
| USUPY | Lupton City | TN |
| USLRY | Luray | TN |
| USLRA | Luray | VA |
| US3LU | Lusby | MD |
| USLSK | Lusk | WY |
| USLUH | Lutcher | LA |
| USLS9 | Luther | MS |
| USLU4 | Luther | OK |
| USL2B | Luthersburg | PA |
| USVUC | Lucan | MN |
| USLCC | Lucas | KS |
| USLV9 | Lucasville | OH |
| USLCU | Lucedale | MS |
| USXZC | Lucerne | CO |
| USLCB | Lucerne Valley | CA |
| USLUC | Luck | WI |
| USLU2 | Luckey | OH |
| USLDM | Ludington | MI |
| USLLW | Ludlow | KY |
| USLUW | Ludlow | MA |
| USULD | Ludlow | MS |
| USUDW | Ludlow | VT |
| USLFK | Lufkin | TX |
| USLOF | Lugoff | SC |
| USLUK | Luke | MD |
| USLUD | Lukeville | AZ |
| USYLU | Lula | GA |
| USLYG | Luling | LA |
| USULG | Luling | TX |
| USJWV | Lowellville | OH |
| USLB7 | Lower Brule | SD |
| US9LL | Lower Lake | CA |
| USLW8 | Lower Waterford | VT |
| USLXP | Lowgap | NC |
| USLLQ | Lowland | TN |
| USLQL | Lowmansville | KY |
| USZG5 | Lowmoor | VA |
| USJDB | Lowndesboro | AL |
| USLWF | Lowville | NY |
| USLXC | Loxahatchee | FL |
| USLXY | Loxley | AL |
| USLY7 | Loyal | WI |
| USLY4 | Loyalhanna | PA |
| USTJL | Loyalton | CA |
| USL7O | Loysville | PA |
| USLUN | Luana | IA |
| USLBB | Lubbock | TX |