| Code | Name | Region |
|---|---|---|
| USMJL | Moscow | ID |
| USZGC | Moscow | KS |
| USQMA | Moscow | PA |
| US9MW | Moscow | TN |
| USM7C | Moscow | TX |
| USMM4 | Moscow Mills | MO |
| USM9S | Mosel | WI |
| USIQS | Morris | PA |
| USMPA | Morris Plains | NJ |
| USMJE | Morrison | CO |
| USMMQ | Morrison | IL |
| USMJF | Morrison | TN |
| USM5V | Morrisonville | IL |
| US6MT | Morriston | FL |
| USMJG | Morristown | IN |
| USMW8 | Morristown | MN |
| USMMU | Morristown | NJ |
| USMRT | Morristown | NY |
| USITW | Morristown | OH |
| USMOR | Morristown | TN |
| USXZM | Morrisville | NC |
| USMV9 | Morrisville | NJ |
| USMZL | Morrisville | NY |
| USXIO | Morrisville | PA |
| USORS | Morrisville | VT |
| USMJK | Morro Bay | CA |
| USMRW | Morrow | GA |
| USVJM | Morganville | NJ |
| USMY5 | Moriarty | NM |
| USZH6 | Moriches | NJ |
| US2MR | Moriches | NY |
| USJGM | Morley | MO |
| USOYO | Moro | AR |
| USO4O | Moro | IL |
| USXOO | Moro | OR |
| USOOC | Morocco | ID |
| USMR6 | Moroni | UT |
| USMJC | Morral | OH |
| USXWQ | Morrice | MI |
| USRQR | Morrill | ME |
| USMOK | Morrill | NE |
| USMPJ | Morrilton | AR |
| USXRI | Morris | AL |
| USMR4 | Morris | CT |
| USMSW | Morris | IL |
| USMR3 | Morris | LA |
| USMOX | Morris | MN |
| USM9V | Moretown | VT |
| USNGM | Morgan | GA |
| USMRG | Morgan | MT |