- Merlin
- Merrills Landing
- Merrimac
- Merritt
- Merritt Island
- Merryman
- Mesa
- Mesa Camp
- Mesa Grande
- Mesa Oaks
- Mesa Verde
- Mesa Vista
- Mesaville
- Mescalitan Island
- Mesquite
- Mesquite Oasis
- Metropolitan
- Mettah
- Mettler
- Metz
- Mexican Colony
- Meyers
- Meyers Place
- Meyers Place
- Mi-Wuk Village
- Michigan Bluff
- Midas
- Midco
- Middle Anacapa Island
- Middle Farallon