Johnson County Address Data

  • State: Illinois
  • County: Johnson County
  • County Seat: Vienna
  • FIPS: 17087
  • Founded in: 1812
  • Population: 12,456
  • Density: 36 Persons/Square Mile
  • Area: 343 Square Miles
  • Government Type: County
  • Authority: Dillon's Rule
  • Legislative Body: Board of Commissioners
  • Legislative Body Size: 3
  • County Contact: PO BOX 96
    County Courthouse
    Vienna, IL 62995-0096
  • Labor Force: 4,100
  • Unemployment Rate: 7.80%
  • Gross Domestic Product (GDP): $227.0 M

Top Cities in Johnson County

Major Cities (population)

Neighbor Counties

  • Massac County
  • Pope County
  • Pulaski County
  • Saline County
  • Union County
  • Williamson County
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