| Code | Name | Region |
|---|---|---|
| USLU3 | Lotus | CA |
| USN3L | Loudon | NH |
| USXHU | Loudon | TN |
| USQYL | Loudonville | NY |
| USLUO | Loudonville | OH |
| USOIJ | Louin | MS |
| USKZY | Louisa | KY |
| USLOW | Louisa | VA |
| USUIJ | Louisburg | KS |
| USUIM | Louisburg | MO |
| USLFN | Louisburg | NC |
| USLOU | Louise | TX |
| USLT8 | Loretto | TN |
| USL6D | Lorida | FL |
| USL9O | Lorimor | IA |
| USWLR | Loring | AK |
| USLRZ | Loris | SC |
| USLR8 | Lorraine | KS |
| USLPV | Lorton | VA |
| USLAT | Los Alamitos | CA |
| USXYL | Los Alamos | CA |
| USLAM | Los Alamos | NM |
| USLLT | Los Altos | CA |
| USLAH | Los Altos Hills | CA |
| USLAX | Los Angeles | CA |
| USLSN | Los Banos | CA |
| USOFS | Los Fresnos | TX |
| USLXX | Los Gatos | CA |
| USLII | Los Indios | TX |
| USLLU | Los Lunas | NM |
| USIOS | Los Molinos | CA |
| USLNE | Los Nietos | CA |
| USL8D | Lonsdale | MN |
| USLT3 | Loogootee | IN |
| USLM6 | Lookout Mountain | GA |
| USZEJ | Lookout Mountain | TN |
| USOXZ | Loomis | CA |
| US7OO | Loomis | NE |
| US2LO | Loop | TX |
| USLO9 | Loop Terminal | LA |
| US3LC | Loose Creek | MO |
| USLJP | Lopatcong | NJ |
| USLPS | Lopez Island | WA |
| USLOR | Lorain | OH |
| USLSB | Lordsburg | NM |
| USLLO | Lordstown | OH |
| USLUX | Loreauville | LA |
| USN6L | Lorena | TX |
| USL5T | Lorenzo | TX |
| USTKY | Loretto | KY |