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 50659 New Hampton Chickasaw County 563, 641
IA 50660 New Hartford Butler County 319
IA 50661 North Washington Chickasaw County 641
IA 50662 Oelwein Fayette County 319, 563
IA 50664 Oran Fayette County 319
IA 50665 Parkersburg Butler County 319
IA 50666 Plainfield Bremer County 319, 641
IA 50667 Raymond Black Hawk County 319
IA 50668 Readlyn Bremer County 319, 563
IA 50669 Reinbeck Grundy County 319, 641
Page 45 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.