M
- (Northumberland County) Manuels
- (Northumberland County) Millbank
- (Northumberland County) Maple Glen
- (Northumberland County) Morrison Cove
- (Northumberland County) Moorefield
- (Victoria County) McManus Siding
- (Madawaska County) Martin Siding
- (Madawaska County) Miller Line Cache
- (Madawaska County) Montagne-des-Therrien
- (Madawaska County) Montagne-de-la-Croix
- (Madawaska County) Montagne-des-Roy
- (Madawaska County) Madawaska Maliseet First Nation
- (Carleton County) McKenna
- (Gloucester County) Madran
- (Gloucester County) Maltempec
- (Gloucester County) Miscou
- (Gloucester County) Maisonnette
- (Westmorland County) McEwen
- (Northumberland County) Miramichi
- (Westmorland County) Moncton