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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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Sioux County ZIP Codes

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

County State ZIP Code City Area Codes
Sioux County IA 51003 Alton 712
Sioux County IA 51011 Chatsworth 712
Sioux County IA 51022 Granville 712
Sioux County IA 51023 Hawarden 605, 712
Sioux County IA 51027 Ireton 712
Sioux County IA 51036 Maurice 712
Sioux County IA 51041 Orange City 712
Sioux County IA 51234 Boyden 712
Sioux County IA 51238 Hospers 712
Sioux County IA 51239 Hull 712
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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.