County ProfileIL
Knox County
Population: 49,967 · 17 ZIP codes
Demographics
Source: U.S. Census Bureau (ACS/Decennial). Estimates vary by year.
People
Total population
49,967
People
Median age
42.6
Housing
Total households
20,972
Income
Median household income
$57,030
Housing
Total housing units
23,758
Employment
Employment rate
52.5%
Education
Bachelor’s degree or higher
21%
Healthcare
Insured population
95%
County details
Local time 04:43:55(CT)| Name | Knox |
|---|---|
| Total ZIP codes | 17total |
| ZIP codes (by type) | 15 Standard2 PO Box |
| Area code | 309, 861 |
| Timezone | Central Time (CT) |
| Coordinates | 40.9309446, -90.2137921 |
| Land area | 716.4 sq miles(1,855.4 km²) |
Map of Knox county, Illinois with ZIP codes
Cities and Communities in Knox County
Compare the largest cities in Knox County by population, median income, and growth. Use the table below to analyze key demographic shifts across the region.
| City | Population | Median incomeHousehold | ZIP codes |
|---|---|---|---|
| Galesburg | 30,052 | $48,297 | 2ZIPs |
| Abingdon | 2,951 | $61,653 | 1ZIPs |
| Knoxville | 2,901 | $82,863 | 1ZIPs |
| Dahinda | 1,125 | — | 1ZIPs |
| East Galesburg | 763 | $79,333 | 1ZIPs |
| Wataga | 744 | $62,917 | 1ZIPs |
| Oneida | 696 | $66,791 | 1ZIPs |
| Yates City | 642 | $63,750 | 1ZIPs |
| Williamsfield | 575 | $82,417 | 1ZIPs |
| Altona | 463 | $69,375 | 1ZIPs |
| Victoria | 268 | $59,375 | 1ZIPs |
| Henderson | 266 | $57,875 | 1ZIPs |
| Maquon | 218 | $63,125 | 1ZIPs |
| Rio | 209 | $72,500 | 1ZIPs |
| Gilson | 156 | $44,531 | 1ZIPs |
| Saint Augustine | 119 | — | 1ZIPs |
— Data unavailable or suppressed by the U.S. Census Bureau for areas with small sample sizes to protect individual privacy.
ZIP Codes in Knox County
Review the most populated postal areas across Knox County. Use the ranking below to compare resident density and demographic scales between the county's major zones.
| ZIP | City | Median incomeHousehold | Population (ZIP) |
|---|---|---|---|
| 61401 | Galesburg | $50,546 | 31,169 |
| 61448 | Knoxville | $82,500 | 3,794 |
| 61410 | Abingdon | $62,925 | 3,632 |
| 61402 | Galesburg | — | 1,589 |
| 61428 | Dahinda | $77,143 | 1,125 |
| 61467 | Oneida | $88,472 | 1,069 |
| 61488 | Wataga | $68,333 | 1,019 |
| 61572 | Yates City | $73,125 | 997 |
| 61489 | Williamsfield | $98,125 | 915 |
| 61436 | Gilson | $76,000 | 840 |
| 61414 | Altona | $48,929 | 782 |
| 61430 | East Galesburg | $79,333 | 753 |
| 61458 | Maquon | $65,461 | 672 |
| 61472 | Rio | $76,500 | 614 |
| 61485 | Victoria | $59,306 | 541 |
| 61474 | Saint Augustine | $59,583 | 282 |
| 61439 | Henderson | $59,125 | 274 |
Data Sources & Citations
The geographic and demographic information presented on this site is compiled from publicly available, authoritative sources, including:
- United States Census BureauDemographic, population, housing, and socioeconomic data sourced from Census Bureau datasets, including the Decennial Census and the American Community Survey (ACS).Census Data
- United States Postal Service (USPS)ZIP code classifications, delivery types, and postal designations used for reference purposes. USPS ZIP codes are intended for mail delivery and may not always align exactly with Census geographic boundaries.USPS