Lewis County, Missouri

Lewis County
Lewis County Courthouse in Monticello
Location within the U.S. state of Missouri
Missouri's location within the U.S.
Coordinates: 40°05′N 91°44′W / 40.09°N 91.73°W / 40.09; -91.73
Country United States
State Missouri
FoundedJanuary 2, 1833
Named afterMeriwether Lewis
SeatMonticello
Largest cityCanton
Area
  Total
511 sq mi (1,320 km2)
  Land505 sq mi (1,310 km2)
  Water5.8 sq mi (15 km2)  1.1%
Population
 (2020)
  Total
10,032
  Estimate 
(2024)
9,852
  Density19.5/sq mi (7.5/km2)
Time zoneUTC−6 (Central)
  Summer (DST)UTC−5 (CDT)
Congressional district6th
Websitelewiscountymo.org

Lewis County is a county located in the northeastern portion of the U.S. state of Missouri. As of the 2020 census, the population was 10,032. Its county seat is Monticello. The county was organized January 2, 1833, and named for Meriwether Lewis, the explorer and Governor of the Louisiana Territory.

Lewis County is part of the Quincy, ILMO Micropolitan Statistical Area.