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
Maps and coordinates
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 50648 Jesup Buchanan County 319
IA 50649 Kesley Butler County 641
IA 50650 Lamont Buchanan County 319, 563
IA 50651 La Porte City Black Hawk County 319
IA 50652 Lincoln Tama County 319, 641
IA 50653 Marble Rock Floyd County 641
IA 50654 Masonville Delaware County 319, 563
IA 50655 Maynard Fayette County 319, 563
IA 50657 Morrison Grundy County 319
IA 50658 Nashua Chickasaw County 319, 641
Page 44 of 107

Geographic Map of Iowa

Postal context

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.