Boone County, Illinois ZIP Codes

5 ZIP Codes

Zip Code
City
Population ↓
61008Belvidere33,582
61065Poplar Grove10,570
61011Caledonia2,676
61012Capron2,264
61038Garden Prairie1,274

Overview of ZIP Codes in Boone County

ZCTAs are geographic areas created by the US Census Bureau to approximate the delivery areas of ZIP Codes for statistical analysis. While ZCTAs use the same five-digit codes as ZIP Codes, they represent defined geographic areas that may not exactly match the mail delivery routes of ZIP Codes.
5
ZIP Codes

The data shown reflect ZCTAs from the US Census. As of 2025, there are 5 ZCTAs in Boone County, Illinois (US Census).

Sources

  1. US Census: 2025 Gazetteer Files
  2. US Census: ZIP Code Tabulation Areas (ZCTAs)

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