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

Colorado ZIP Codes

Complete postal directory, details, and geographic map for the State of Colorado.

State ZIP Code City County Area Codes
CO 80536 Livermore Larimer County 307, 970
CO 80537 Loveland Larimer County 303, 720, 970, 983
CO 80538 Loveland Larimer County 970
CO 80539 Loveland Larimer County 970
CO 80540 Lyons Boulder County 303, 720, 970, 983
CO 80541 Masonville Larimer County 970
CO 80542 Mead Weld County 303, 720, 970, 983
CO 80543 Milliken Weld County 970
CO 80544 Niwot Boulder County 303, 720, 983
CO 80545 Red Feather Lakes Larimer County 307, 970
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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.