Mercer County ZIP Codes
Illinois, United States · 12 codes
Mercer County in Illinois has 12 ZIP codes, from 61231 to 61486, serving 12 places.
ZIP codes in Mercer
Frequently asked questions
What is the ZIP code of Mercer?
Mercer has 12 ZIP codes, from 61231 to 61486. The table lists the places each one serves.
How many places are listed in Mercer County?
12 places.
Source: GeoNames postal codes (CC BY 4.0), geonames.org, retrieved 2026-10-22. Place coordinates are approximate. Check with the national postal service before sending anything valuable.