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U.S. ZIP Codes Database 2026

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Keokuk County ZIP Codes

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

County State ZIP Code City Area Codes
Keokuk County IA 50104 Gibson 641
Keokuk County IA 50136 Keswick 319, 641
Keokuk County IA 50255 Thornburg 641
Keokuk County IA 50268 What Cheer 319, 641
Keokuk County IA 52231 Harper 319, 641
Keokuk County IA 52248 Keota 319, 641
Keokuk County IA 52335 South English 319, 641
Keokuk County IA 52355 Webster 319, 641
Keokuk County IA 52550 Delta 641
Keokuk County IA 52562 Hayesville 641
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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.