| Code | Name | Region |
|---|---|---|
| USMJB | Mount Juliet | TN |
| USMKS | Mount Kisco | NY |
| USLUJ | Mount Laurel | NJ |
| USMCL | Mount Mckinley | AK |
| USOUM | Mount Meigs | AL |
| USMXR | Mount Morris | IL |
| USMMB | Mount Morris | MI |
| USTBK | Mount Braddock | PA |
| USMC6 | Mount Carmel | IL |
| USMTK | Mount Carmel | PA |
| USKRL | Mount Carroll | IL |
| USMTC | Mount Clemens | MI |
| USMWR | Mount Crawford | VA |
| USDZT | Mount Desert | ME |
| USMUD | Mount Dora | FL |
| USME2 | Mount Eaton | OH |
| USM3E | Mount Eden | KY |
| USIUE | Mount Erie | IL |
| USM3F | Mount Freedom | NJ |
| USMGQ | Mount Gilead | NC |
| USUGO | Mount Gilead | OH |
| USM5G | Mount Gretna | PA |
| USTBO | Mount Hebron | MD |
| USNHR | Mount Hermon | CA |
| USMH6 | Mount Holly | AR |
| USMHX | Mount Holly | NC |
| USLLY | Mount Holly | NJ |
| US4MC | Mound City | IL |
| USM9C | Mound City | MO |
| USXZS | Mound House | NV |
| USMDZ | Moundridge | KS |
| US7Q9 | Mounds | IL |
| USOUK | Mounds | OK |
| USMJO | Mounds View | MN |
| USMFZ | Moundsville | WV |
| USMOA | Moundville | AL |
| USND5 | Moundville | MO |
| USNQU | Mount Airy | GA |
| USM8Y | Mount Airy | LA |
| USMYM | Mount Airy | MD |
| USMKY | Mount Airy | NC |
| USOMO | Mount Angel | OR |
| USUNM | Mount Arlington | NJ |
| USOUA | Mount Ayr | IA |
| USMJR | Mount Berry | GA |
| USMB5 | Mount Bethel | PA |
| USMXT | Mount Bethel | PA |
| USOEL | Moselle | MS |
| USKMY | Moser Bay | AK |
| USMWH | Moses Lake | WA |