| Massac County, IL (County) |
| Massachusetts, MA (State) |
| Massapequa Park, NY (Village) |
| Massena, NY (Village) |
| Massena, IA (City) |
| Massena, NY (Town) |
| Massena Township, IA (Township) |
| Massie Township, OH (Township) |
| Massillon, OH (City) |
| Massillon Township, IA (Township) |
| Massilon Township, IL (Township) |
| Mastic Beach, NY (Village) |
| Mastodon Township, MI (Township) |
| Matador, TX (Town) |
| Matagorda County, TX (County) |
