13 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 61231 | Aledo | 5,158 |
| 61281 | Sherrard | 2,553 |
| 61486 | Viola | 1,450 |
| 61272 | New Boston | 1,357 |
| 61465 | New Windsor | 1,250 |
| 61412 | Alexis | 1,154 |
| 61279 | Reynolds | 944 |
| 61263 | Matherville | 808 |
| 61442 | Keithsburg | 678 |
| 61476 | Seaton | 605 |
| 61260 | Joy | 595 |
| 61466 | North Henderson | 267 |
| 61276 | Preemption | 77 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 13 ZCTAs in Mercer County, Illinois (US Census).