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

Washington County ZIP Codes

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

County State ZIP Code City Area Codes
Washington County ME 04694 Baileyville 207, 506
Washington County MN 55001 Afton 534, 651, 715
Washington County MN 55003 Bayport 534, 651, 715
Washington County MN 55016 Cottage Grove 651
Washington County MN 55025 Forest Lake 651, 763
Washington County MN 55038 Hugo 651, 763
Washington County MN 55042 Lake Elmo 651
Washington County MN 55043 Lakeland 534, 651, 715
Washington County MN 55047 Marine On Saint Croix 534, 651, 715
Washington County MN 55055 Newport 651
Page 16 of 45

Geographic Map of Washington 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.