McDonough County, Illinois

McDonough County
Location within the U.S. state of Illinois
Illinois's location within the U.S.
Coordinates: 40°28′N 90°41′W / 40.46°N 90.68°W / 40.46; -90.68
Country United States
State Illinois
FoundedJanuary 25, 1826
Named afterThomas Macdonough
SeatMacomb
Largest cityMacomb
Area
  Total
590 sq mi (1,500 km2)
  Land589 sq mi (1,530 km2)
  Water0.8 sq mi (2 km2)  0.1%
Population
 (2020)
  Total
27,238
  Density46/sq mi (18/km2)
Time zoneUTC−6 (Central)
  Summer (DST)UTC−5 (CDT)
Congressional districts15th, 17th
Websitemcg.mcdonough.il.us

McDonough County is a county in the U.S. state of Illinois. According to the 2020 census, it had a population of 27,238. Its county seat is Macomb, which is also the home of Western Illinois University.

McDonough County is part of the Macomb, IL Micropolitan Statistical Area.