Sangamon County, Illinois

Sangamon County
Location within the U.S. state of Illinois
Illinois's location within the U.S.
Coordinates: 39°46′N 89°40′W / 39.76°N 89.66°W / 39.76; -89.66
Country United States
State Illinois
Founded1821
Named afterSangamon River
SeatSpringfield
Largest citySpringfield
Area
  Total
877 sq mi (2,270 km2)
  Land868 sq mi (2,250 km2)
  Water8.7 sq mi (23 km2)  1.0%
Population
 (2020)
  Total
196,343
  Density220/sq mi (86/km2)
Congressional districts13th, 15th
Websitewww.co.sangamon.il.us

Sangamon County is a county located near the center of the U.S. state of Illinois. According to the 2020 census, it had a population of 196,343. Its county seat and largest city is Springfield, the state capital.

Sangamon County is included in the Springfield, IL Metropolitan Statistical Area.