- Mulberry Island
- Marissa
- Mark
- Maroa
- Marquette Heights
- Martinton
- Mascoutah
- Matherville
- Matteson
- Mattoon
- Maunie
- Mazon
- McCullom Lake
- McKinley
- McHenry
- Mayberry
- Merriam
- Middleton
- McLeansboro
- McNabb
- Medora
- Meredosia
- Marion Mobile Home Village
- Merrionette Park
- Metcalf
- Metropolis
- Mettawa
- Midlothian
- Mill Shoals
- Mancuso Village Park