- MacIntosh Mill
- Macs Island
- Madawaska Maliseet First Nation
- Madran
- Mainstream
- Maisonnette
- Malauze
- Maltais
- Maltempec
- Man of War Island
- Manawagonish Island
- Mann Mountain Settlement
- Mann Siding
- Manuels
- Maple Glen
- Maple Green
- Maple Grove
- Maple Grove Station
- Maple Ridge
- Mapledale
- Maplehurst
- Mapleview
- Maplewood
- Marble Island
- Martin Siding
- Mather Island
- Mavis Mills
- McAdam
- McCluskey
- McEwen