US Gazetteer > Illinois Gazetteer > Illinois ZIP Codes > County ZIP Codes > Mercer ZIP Codes

ZIP Codes in Mercer County with Associated Cities & Towns

Aledo   61231
Alexis   61412
Joy   61260
Keithsburg   61442
Matherville   61263
 N Henderson   61466
New Boston   61272
New Windsor   61465
North Henderson   61466
 Preemption   61276
Seaton   61476
Sherrard   61281
Viola   61486

ZIP Codes - Key Concepts

  1. ZIP Codes are categories for grouping mailing addresses and are not exact geographic regions.
  2. The centroid of a ZIP Code may be in one County and the associated city/town in another.
  3. In rural areas, a single ZIP Code may be used for cities and towns in several different Counties.
  4. ZIP Code "areas" can overlap, be subsets of each other, or be artificial constructs with no geographic area.
  5. ZIP Codes are only loosely tied to cities.