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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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Mills County ZIP Codes

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

County State ZIP Code City Area Codes
Mills County IA 51533 Emerson 712
Mills County IA 51534 Glenwood 712
Mills County IA 51540 Hastings 712
Mills County IA 51541 Henderson 712
Mills County IA 51551 Malvern 712
Mills County IA 51554 Mineola 712
Mills County IA 51561 Pacific Junction 402, 531, 712
Mills County IA 51571 Silver City 712
Roger Mills County OK 73628 Cheyenne 580
Roger Mills County OK 73638 Crawford 580
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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.