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
County directory

Keokuk County ZIP Codes

Browse all ZIP Codes, cities, and associated area codes registered in Keokuk County.

County State ZIP Code City Area Codes
Keokuk County IA 52563 Hedrick 319, 641
Keokuk County IA 52568 Martinsburg 641
Keokuk County IA 52576 Ollie 319, 641
Keokuk County IA 52585 Richland 319, 641
Keokuk County IA 52591 Sigourney 319, 641
Page 2 of 2

Geographic Map of Keokuk County

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.