- Mound Key
- Mar Lago Village
- Margate Estates
- Melalevca Isles
- Melrose Park (historical)
- Mickey's Mobile Home Park
- Middle River
- Middle River Manor
- Middle River Trailer Park
- Middle River Vista
- Moonlight Ranch Mobile Home Park
- Marysville
- Mendit Key
- Mullet Key
- Magnolia Springs
- Meadowbrook Terrace
- M and E Trailer Park
- Marco Island
- Marco Shores Estates Mobile Home Park
- Margaret Key
- Miraham Trailer Park
- Morgan Island
- Morgan Key
- Munlin Island
- Mason
- McColskey
- McColsky
- Mikesville
- Miltons Campground Number 1
- Mount Carrie