COUNTY · IL
Logan County, Illinois
Logan County is a county in Illinois with FIPS code 17107 and an estimated population of 27,590 (Census 2023), 49th largest of 102 in the state.
County facts
- Name
- Logan County
- State
- Illinois
- Type
- county
- FIPS code
- 17107
- State FIPS
- 17
- Population (2023)
- 27,590
- Change since 2020
- -1.2%
- State rank
- 49 of 102
Population is the Census Bureau’s Vintage 2023 estimate.
Questions
What is the FIPS code for Logan County?
Logan County, Illinois has the five-digit FIPS code 17107: 17 for the state and 107 for the county.
What state is Logan County in?
Logan County is in Illinois.
How do I know if an address is in this county?
Use the address lookup. ZIP codes and city names can cross county lines, so an address is the reliable check.
Sources: U.S. Census Bureau geographic reference files; Census Bureau Population Estimates, Vintage 2023. Last reviewed 2026-10-27.