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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.

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Jefferson County ZIP Codes

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

County State ZIP Code City Area Codes
Jefferson County CO 80036 Westminster 303
Jefferson County CO 80123 Littleton 303, 720, 983
Jefferson County CO 80127 Littleton 303, 720, 983
Jefferson County CO 80128 Littleton 303, 720, 983
Jefferson County CO 80214 Denver 303, 720, 983
Jefferson County CO 80215 Denver 303, 720, 983
Jefferson County CO 80226 Denver 303, 720, 983
Jefferson County CO 80227 Denver 303, 720, 983
Jefferson County CO 80228 Denver 303, 720, 983
Jefferson County CO 80232 Denver 303, 720, 983
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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.