Mercer County, Illinois
Mercer County is a county in Illinois. Its county FIPS code is 17131. Use the boundary map and neighboring areas below to check the jurisdiction you need.
- Official code
- 17131
- Representative coordinates
- 41.205605, -90.741770
- County type
- County
- County seat or government
- Aledo
- Resident population, July 2025
- 15,229
- Land area
- 1,453.604 km²
- Water area
- 19.412 km²
- State
- Illinois
The representative point identifies this area. It is not a street address or a boundary survey.
Time zones in Mercer 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
61231 · 61259 · 61260 · 61262 · 61263 · 61264 · 61272 · 61273 · 61276 · 61279 · 61281 · 61412 · 61442 · 61465 · 61466 · 61472 · 61476 · 61486
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.
- Aledo city, IL
- Alexis village, IL
- Cable CDP, IL
- Eliza CDP, IL
- Hamlet CDP, IL
- Joy village, IL
- Keithsburg city, IL
- Matherville village, IL
- Millersburg CDP, IL
- New Boston city, IL
- North Henderson village, IL
- Preemption CDP, IL
- Reynolds village, IL
- Seaton village, IL
- Sherrard village, IL
- Swedona CDP, IL
- Viola village, IL
- Windsor village, IL
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.