Marion County, Illinois
Marion County is a county in Illinois. Its county FIPS code is 17121. Use the boundary map and neighboring areas below to check the jurisdiction you need.
- Official code
- 17121
- Representative coordinates
- 38.648236, -88.920362
- County type
- County
- County seat or government
- Salem
- Resident population, July 2025
- 36,382
- Land area
- 1,482.867 km²
- Water area
- 9.233 km²
- State
- Illinois
The representative point identifies this area. It is not a street address or a boundary survey.
Time zones in Marion County
| Time zone | Local time and UTC offset | Next clock change |
|---|---|---|
| America/Chicago | UTC-06:00 in January; UTC-05:00 in July. Enable JavaScript for the live clock. | Enable JavaScript for upcoming changes. |
Listed zones overlap the mapped area. A point lookup can distinguish sides of a boundary. Your device’s zone may differ.
Census ZIP areas
62801 · 62807 · 62830 · 62838 · 62849 · 62851 · 62853 · 62854 · 62870 · 62875 · 62881 · 62882 · 62889 · 62892 · 62893
These statistical areas overlap the boundary. They are not delivery assignments; confirm mailing details with USPS ZIP Code Lookup.
Official county information
Use the US government local-office directory ↗ to find the office responsible for your address. A county website has not been confidently matched here. A geographic lookup cannot determine eligibility, tax liability or a court obligation.
Cities, towns and communities
These areas overlap the mapped boundary; an overlap does not mean that every address belongs to both.
Areas sharing the mapped boundary
These areas touch this mapped boundary.
Before using this answer on a form
Use a precise point for address-level questions. A device accuracy circle can cross a boundary; confirm tax, voting or jury details with the responsible office.
Find the county at your current point, check its ZIP area, or find its physical time zone.