Places beginning with MO in Illinois, United States
- Mobil-Land Trailer Park (subdivision)
- Moccasin
- Moccasin, Township of
- Mode
- Modena
- Modesto
- Modoc
- Moellenbrocks
- Mokena
- Moline
- Moline, Township of
- Momence
- Momence, Township of
- Mona, Township of
- Monaville
- Monee
- Monee, Township of
- Money Creek, Township of
- Monica
- Monmouth
- Monmouth, Township of
- Monroe Center
- Monroe City
- Monroe County
- Monroe Election Precinct
- Monroe, Township of
- Montclare (subdivision)
- Montebello, Township of
- Monterey
- Montezuma
- Montezuma, Township of
- Montgomery
- Montgomery County
- Montgomery, Township of
- Montgomery, Township of
- Monticello
- Monticello, Township of
- Montmorency, Township of
- Montrose
- Montrose (subdivision)
- Mont Station
- Moonshine
- Moorefield Estates
- Moores Corner
- Moores (historical)
- Moores Prairie, Township of
- Mooseheart
- Moraine, Township of
- Moran Corners
- Morea
- Morehaven
- Moreland (subdivision)
- Morgan City (historical)
- Morgan County
- Morgan Park (subdivision)
- Morgan, Township of
- Morganville
- Moriah
- Moro
- Moronts
- Moro, Township of
- Morrelville
- Morris
- Morris Kennedy Subdivision (subdivision)
- Morrison
- Morrisonville
- Morristown
- Morristown (historical)
- Morris, Township of
- Morse
- Morseville
- Mortimer
- Morton
- Morton Grove
- Morton, Township of
- Moscow
- Moscow (historical)
- Mosquito, Township of
- Mossville
- Motor Heights (subdivision)
- Moultrie County
- Mound City
- Mound City Election Precinct
- Mounds
- Mounds Election Precinct
- Mound, Township of
- Mound, Township of
- Mountain Glen
- Mountain, Township of
- Mount Auburn
- Mount Auburn, Township of
- Mount Carbon
- Mount Carmel
- Mount Carmel Election Precinct
- Mount Carroll
- Mount Carroll, Township of
- Mount Clare
- Mount Erie
- Mount Erie, Township of
- Mount Fulcher
- Mount Greenwood (subdivision)
- Mount Hope, Township of
- Mountjoy
- Mount Morris
- Mount Morris, Township of
- Mount Olive
- Mount Olive, Township of
- Mount Palatine
- Mount Pleasant
- Mount Pleasant (subdivision)
- Mount Pleasant, Township of
- Mount Prospect
- Mount Pulaski
- Mount Pulaski, Township of
- Mount Sterling
- Mount Sterling, Township of
- Mount Vernon
- Mount Vernon, Township of
- Mount Zion
- Mount Zion, Township of
- Moweaqua
- Moweaqua, Township of
- Mozier
- Mozier Landing