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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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Winneshiek County ZIP Codes

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

County State ZIP Code City Area Codes
Winneshiek County IA 52101 Decorah 507, 563
Winneshiek County IA 52132 Calmar 563
Winneshiek County IA 52133 Castalia 563
Winneshiek County IA 52144 Fort Atkinson 563
Winneshiek County IA 52149 Highlandville 563
Winneshiek County IA 52161 Ossian 563
Winneshiek County IA 52165 Ridgeway 563
Winneshiek County IA 52168 Spillville 563

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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.