Warren County, Ohio

Warren County
County
Warren County Administration Building in Lebanon, Ohio
Flag Seal
Location within the U.S. state of Ohio
Ohio's location within the U.S.
Coordinates: 39°26′N 84°10′W / 39.43°N 84.17°W / 39.43; -84.17
Country	United States
State	Ohio
Founded	May 1, 1803[1]
Named for	Dr. Joseph Warren
Seat	Lebanon
Largest city	Mason
Area
• Total	407 sq mi (1,050 km2)
• Land	401 sq mi (1,040 km2)
• Water	6.0 sq mi (16 km2)  1.5%
Population  (2020)
• Total	242,337
• Estimate  (2021)	246,553
• Density	600/sq mi (230/km2)
Time zone	UTC−5 (Eastern)
• Summer (DST)	UTC−4 (EDT)
Congressional district	1st
Website	www.co.warren.oh.us

Warren County is a county located in the southwestern part of the U.S. state of Ohio. As of the 2020 census, the population was 242,337.^[2] Its county seat is Lebanon and largest city is Mason.^[3] The county is one of Ohio's most affluent, with the highest median income of the state's 88 counties. The county was established on May 1, 1803, from Hamilton County; it is named for Dr. Joseph Warren, a hero of the Revolution who sent Paul Revere and the overlooked William Dawes on their famous rides and who died at the Battle of Bunker Hill.^[4] Warren County is part of the Cincinnati, OH-KY-IN Metropolitan Statistical Area.