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

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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	51244	Matlock	Sioux County	`712`
IA	51245	Primghar	O'Brien County	`712`
IA	51246	Rock Rapids	Lyon County	`507, 712`
IA	51247	Rock Valley	Sioux County	`605, 712`
IA	51248	Sanborn	O'Brien County	`712`
IA	51249	Sibley	Osceola County	`507, 712`
IA	51250	Sioux Center	Sioux County	`712`
IA	51301	Spencer	Clay County	`712`
IA	51331	Arnolds Park	Dickinson County	`712`
IA	51333	Dickens	Clay County	`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.