- Marshall Junction
- Marshfield
- Marston
- Marthasville
- Martin City
- Martinsburg
- Martinstown
- Martinsville
- Marvel Cave
- Marvin
- Mary Ridge
- Maryknoll
- Maryland Heights
- Marys Home
- Maryville
- Mascot
- Massie Island
- Masters
- Masters Island
- Mathis
- Matkins
- Matney
- Matson
- Mattese
- Matthews
- Maud
- Maulsby
- Maupin
- Maurine
- Mauser Mill