St. Charles County, Missouri

"St. Charles County" redirects here. For the similarly-named Louisiana parish, see St. Charles Parish, Louisiana.

St. Charles County
County
St. Charles County Courthouse in St. Charles
St. Charles County Courthouse in St. Charles
Flag of St. Charles County
Flag
Map of Missouri highlighting St. Charles County
Location within the U.S. state of Missouri
Map of the United States highlighting Missouri
Missouri's location within the U.S.
Coordinates: 38°45′36″N 90°37′00″W / 38.76°N 90.6167°W / 38.76; -90.6167
Country United States
State Missouri
FoundedOctober 1, 1812
Named forCharles Borromeo
SeatSt. Charles
Largest cityO'Fallon
Government
 • County executiveSteve Ehlmann (R)
Area
 • Total593 sq mi (1,540 km2)
 • Land560 sq mi (1,500 km2)
 • Water32 sq mi (80 km2)  5.4%
Population
 (2020)
 • Total405,262
 • Density680/sq mi (260/km2)
Time zoneUTC−6 (Central)
 • Summer (DST)UTC−5 (CDT)
Congressional districts2nd, 3rd
Websitewww.sccmo.org

St. Charles County is a county in the central eastern part of the U.S. state of Missouri. As of the 2020 census, the population was 405,262,[1] making it Missouri's third-most populous county. Its county seat is St. Charles.[2] The county was organized October 1, 1812, and named for Saint Charles Borromeo, an Italian cardinal.

St. Charles County is part of the St. Louis, MO-IL Metropolitan Statistical Area and contains many of the city's northwestern suburbs. The wealthiest county in Missouri,[3] St. Charles County is one of the nation's fastest-growing counties.

St. Charles County includes a part of the Augusta AVA, an area of vineyards and wineries designated by the federal government in 1980 as the first American Viticultural Area.[4] The county's rural outer edge along the south-facing bluffs above the Missouri River, is also part of the broader Missouri Rhineland.

  1. ^ "2020 U.S. Census". United States Census Bureau.
  2. ^ "Find a County". National Association of Counties. Retrieved June 7, 2011.
  3. ^ "County-Level Unemployment and Median Household Income for Missouri". www.ers.usda.gov. USDA Economic Research Service. Retrieved March 30, 2009.
  4. ^ Pingelton, Tim (December 8, 2005). "The Soul of Augusta". Appellation American. Archived from the original on July 24, 2008.