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U.S. ZIP Codes Database 2026

Search by ZIP code, city, county, or state and find clear postal details with maps, time zones, and area code data.

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Winnebago County ZIP Codes

Browse all ZIP Codes, cities, and associated area codes registered in Winnebago County.

County State ZIP Code City Area Codes
Winnebago County IA 50424 Buffalo Center 507, 515, 641
Winnebago County IA 50436 Forest City 641
Winnebago County IA 50450 Lake Mills 507, 641
Winnebago County IA 50453 Leland 641
Winnebago County IA 50465 Rake 507, 641
Winnebago County IA 50473 Scarville 507, 641
Winnebago County IA 50478 Thompson 507, 641
Winnebago County IL 61016 Cherry Valley 779, 815
Winnebago County IL 61024 Durand 608, 779, 815
Winnebago County IL 61063 Pecatonica 779, 815
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About U.S. ZIP Codes

ZIP codes are a United States Postal Service system introduced in 1963 to make mail routing more accurate and efficient. The standard format uses five digits, while ZIP+4 adds four more digits for a more precise delivery segment.

ZIP codes cover the United States, its territories, military mail routes, and other USPS delivery points. This directory organizes that data for practical lookup by ZIP code, city, county, and state.