Platte County, Missouri

Platte County
Platte County Courthouse
Location within the U.S. state of Missouri
Missouri's location within the U.S.
Coordinates: 39°23′N 94°46′W / 39.38°N 94.77°W / 39.38; -94.77
Country United States
State Missouri
FoundedDecember 31, 1838
Named afterPlatte River or Platte Purchase
SeatPlatte City
Largest cityKansas City
Area
  Total
427 sq mi (1,110 km2)
  Land420 sq mi (1,100 km2)
  Water6.6 sq mi (17 km2)  1.5%
Population
 (2020)
  Total
106,718
  Density250/sq mi (96/km2)
Time zoneUTC−6 (Central)
  Summer (DST)UTC−5 (CDT)
Congressional district6th
Websitewww.co.platte.mo.us

Platte County is a county located in the northwestern portion of the U.S. state of Missouri and is part of the Kansas City metropolitan area. As of the 2020 census, the population was 106,718. Its county seat is Platte City. The county was organized December 31, 1838, from the Platte Purchase, named for the Platte River. (Platte is derived from the French word for a low, shallow, or intermittent stream.) The Kansas City International Airport is located in the county, approximately one mile west of Interstate 29 between mile markers 12 and 15. The land for the airport was originally in an unincorporated portion of Platte County before being annexed by Platte City, and eventually Kansas City.