Johnson County, Kansas

Johnson County
Johnson County
County
	Former Johnson County Courthouse in Olathe (2009). It opened in 1952, closed in 2020, then demolished in 2021 after a new courthouse was finished.
	Location within the U.S. state of Kansas
	Kansas's location within the U.S.
	Coordinates: 38°52′N 94°52′W / 38.867°N 94.867°W
Country	United States
State	Kansas
Founded	August 25, 1855
Named for	Thomas Johnson
Seat	Olathe
Largest city	Overland Park
Area
• Total	480 sq mi (1,200 km2)
• Land	473 sq mi (1,230 km2)
• Water	6.5 sq mi (17 km2) 1.4%
Population (2020)
• Total	609,863
• Estimate (2021)	613,219
• Density	1,289.4/sq mi (497.8/km2)
Time zone	UTC−6 (Central)
• Summer (DST)	UTC−5 (CDT)
Congressional district	3rd
Website	jocogov.org

Johnson County is a county in the U.S. state of Kansas, along the border of the state of Missouri. Its county seat is Olathe.^[5] As of the 2020 census, the population was 609,863, the most populous county in Kansas.^[3] The county was named after Thomas Johnson, a Methodist missionary who was one of the state's first settlers. Largely suburban, the county contains a number of suburbs of Kansas City, Missouri, including Overland Park, a principal city of and second most populous city in the Kansas City Metropolitan Area.^[6]^[7]

^ Cite error: The named reference OldCourtHouse was invoked but never defined (see the help page).
^ Cite error: The named reference NewCourtHouse was invoked but never defined (see the help page).
^ ^a ^b "QuickFacts; Johnson County, Kansas; Population, Census, 2020 & 2010". United States Census Bureau. Archived from the original on August 15, 2021. Retrieved August 15, 2021.
^ "Annual Estimates of the Resident Population for Counties: April 1, 2020 to July 1, 2021". Retrieved October 3, 2022.
^ "Fast Facts". Johnson County Kansas. Archived from the original on July 16, 2019.
^ "Home Page". Johnson County Kansas. Retrieved November 20, 2019.
^ McCammon, Sarah (September 4, 2017). "As Kansas City Booms And Sprawls, Trying Not To Forget Those In Between". National Public Radio. Retrieved July 10, 2020.