Piatt County, Illinois

Piatt County
Location within the U.S. state of Illinois
Illinois's location within the U.S.
Coordinates: 40°01′N 88°35′W / 40.01°N 88.59°W / 40.01; -88.59
Country United States
State Illinois
Founded1841
Named afterJames A. Piatt
SeatMonticello
Largest cityMonticello
Area
  Total
439 sq mi (1,140 km2)
  Land439 sq mi (1,140 km2)
  Water0.3 sq mi (0.8 km2)  0.06%
Population
 (2020)
  Total
16,673
  Density38/sq mi (15/km2)
Time zoneUTC−6 (Central)
  Summer (DST)UTC−5 (CDT)
Congressional districts13th, 15th
Websitewww.piattcounty.org

Piatt County is a county in Illinois. According to the 2020 United States census, it had a population of 16,673. Its county seat is Monticello.

Piatt County is part of the Champaign-Urbana Metropolitan Area.