Jefferson County, Ohio

Jefferson County
Location within the U.S. state of Ohio
Ohio's location within the U.S.
Coordinates: 40°23′N 80°46′W / 40.38°N 80.76°W / 40.38; -80.76
Country United States
State Ohio
FoundedJuly 29, 1797
Named afterThomas Jefferson
SeatSteubenville
Largest citySteubenville
Area
  Total
411 sq mi (1,060 km2)
  Land408 sq mi (1,060 km2)
  Water2.6 sq mi (7 km2)  0.6%
Population
 (2020)
  Total
65,249
  Density160/sq mi (60/km2)
Time zoneUTC−5 (Eastern)
  Summer (DST)UTC−4 (EDT)
Congressional district6th
Websitejeffersoncountyoh.com

Jefferson County is a county located in the U.S. state of Ohio. As of the 2020 census, the population was 65,249. Its county seat is Steubenville. The county is named for Thomas Jefferson, who was vice president at the time of its creation.

Jefferson County is part of the Weirton–Steubenville, WV–OH Metropolitan Statistical Area, which is also included in the Pittsburgh–New Castle–Weirton, PA–WV–OH Combined Statistical Area.