U.S. postal lookup

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.

42,735 verified records
All states and U.S. territories
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State directory

Iowa ZIP Codes

Complete postal directory, details, and geographic map for the State of Iowa.

State ZIP Code City County Area Codes
IA 50402 Mason City Cerro Gordo County 641
IA 50420 Alexander Franklin County 641
IA 50421 Belmond Wright County 515, 641
IA 50423 Britt Hancock County 641
IA 50424 Buffalo Center Winnebago County 507, 515, 641
IA 50426 Carpenter Mitchell County 641
IA 50427 Chapin Franklin County 641
IA 50428 Clear Lake Cerro Gordo County 641
IA 50430 Corwith Hancock County 515, 641
IA 50431 Coulter Franklin County 641
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Geographic Map of Iowa

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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.