Zip Code 61257 — Hillsdale, IL
61257 is a ZIP Code associated with Hillsdale, IL, located within Rock Island. 61257 ranks #14 out of 17 ZIP codes in Rock Island County by population (and #961 out of 1,396 in IL). The area supports an estimated population of 844 residents across Data Pending housing units, with a population density of 7.9 people per square mile.
WorldPlaceData database updated: October 2026
📍 View location on OpenStreetMap (41.590250, -90.223220)
| Data Metric | Local Statistic |
|---|
| Postal / Zip Code | 61257 |
| Primary City | Hillsdale |
| State / Province | IL |
| County | Rock Island |
| Total Population | 844 |
| Median Household Income | Data Pending |
| Total Housing Units | Data Pending |
| Population Density | 7.9 people/sq mi |
| Timezone | America/Chicago |
How 61257 Compares
| Metric | ZIP 61257 | Rock Island County | IL State Average |
|---|
| Population | 844 | 143,264 (Total) | 12,694,745 (Total) |
| Average ZIP Income | Data Pending | N/A | N/A |
| Population Density | 7.9 /sq mi | -- | -- |
| County Pop Rank | #14 of 17 | -- | -- |
Nearby ZIP Codes
Data Sources & Methodology: Geographic coordinates and ZIP Code assignments are derived from underlying geographic and postal datasets. Note that ZIP Codes are USPS postal delivery areas, while Census ZCTAs are statistical approximation areas. Read full methodology →