Postal reference / United States
61103Rockford, Illinois
ZIP code 61103 is a United States postal code for Rockford, Illinois. Its county association is Winnebago County. The map reference point is at 42.301, -89.0833.
- State / territory
- Illinois
- Recorded place name
- Rockford
- County association
- Winnebago
- Estimated coordinate
- 42.301, -89.0833
View on OpenStreetMap - ZIP prefix
- 611 · 19 ZIP codes share it
- Data source
- GeoNames postal reference, snapshot September 26, 2026
GeoNames reference data. County associations may not include every intersecting county, place names are postal names rather than legal boundaries, and coordinates are approximate. This is not address validation.
Area
- Land area
- 16.336 sq mi (2023 Census Gazetteer)
Figures are for the ZIP Code Tabulation Area (ZCTA) that most closely matches this ZIP code, not an exact match to USPS delivery boundaries. Source: U.S. Census Bureau, 2023 Gazetteer + 2023 ACS 5-Year Estimates, retrieved 2026-09-27. How to read this data.
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Illinois directoryOther ZIP codes in Rockford, IL
Rockford has 14 ZIP codes in the reference dataset.
Nearby ZIP code reference points
| ZIP code | Place | State | County association | Miles |
|---|---|---|---|---|
| 61101 | Rockford | IL | Winnebago | 1.8 |
| 61105 | Rockford | IL | Winnebago | 2.1 |
| 61107 | Rockford | IL | Winnebago | 2.9 |
| 61104 | Rockford | IL | Winnebago | 3.2 |
| 61111 | Loves Park | IL | Winnebago | 3.2 |
| 61102 | Rockford | IL | Winnebago | 3.8 |
| 61115 | Machesney Park | IL | Winnebago | 4.3 |
| 61114 | Rockford | IL | Winnebago | 4.6 |
Straight-line distance between reference points. Nearby points do not prove that ZIP areas touch.
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