| Zip Code | City | Population ↓ |
|---|---|---|
| 61401 | Galesburg | 30,809 |
| 61448 | Knoxville | 4,076 |
| 61410 | Abingdon | 3,730 |
| 61402 | Galesburg | 1,748 |
| 61488 | Wataga | 1,284 |
| 61467 | Oneida | 1,244 |
| 61428 | Dahinda | 1,162 |
| 61572 | Yates City | 1,029 |
| 61489 | Williamsfield | 841 |
| 61414 | Altona | 794 |
| 61436 | Gilson | 787 |
| 61430 | East Galesburg | 618 |
| 61458 | Maquon | 464 |
| 61472 | Rio | 387 |
| 61485 | Victoria | 387 |
| 61474 | Saint Augustine | 285 |
| 61439 | Henderson | 250 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 17 ZCTAs in Knox County, Illinois (US Census).