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	50548	Humboldt	Humboldt County	`515`
IA	50551	Jolley	Calhoun County	`712`
IA	50552	Knierim	Calhoun County	`515, 712`
IA	50554	Laurens	Pocahontas County	`712`
IA	50556	Ledyard	Kossuth County	`515`
IA	50557	Lehigh	Webster County	`515`
IA	50558	Livermore	Humboldt County	`515`
IA	50559	Lone Rock	Kossuth County	`515`
IA	50560	Lu Verne	Kossuth County	`515`
IA	50561	Lytton	Sac 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.