Stephenson County, Illinois

Stephenson County
Location within the U.S. state of Illinois
Illinois's location within the U.S.
Coordinates: 42°21′N 89°40′W / 42.35°N 89.67°W / 42.35; -89.67
Country United States
State Illinois
Founded1837
Named afterBenjamin Stephenson
SeatFreeport
Largest cityFreeport
Area
  Total
565 sq mi (1,460 km2)
  Land565 sq mi (1,460 km2)
  Water0.5 sq mi (1 km2)  0.09%
Population
 (2020)
  Total
44,630
  Estimate 
(2023)
43,105
  Density79/sq mi (30/km2)
Time zoneUTC−6 (Central)
  Summer (DST)UTC−5 (CDT)
Congressional districts16th, 17th
Websitewww.co.stephenson.il.us

Stephenson County is a county located in the U.S. state of Illinois. According to the 2020 United States census, it had a population of 44,630. Its county seat is Freeport. Stephenson County is included in the Freeport, IL Micropolitan Statistical Area, which is also included in the Rockford-Freeport-Rochelle, IL Combined Statistical Area.