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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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Los Alamos County ZIP Codes

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

County State ZIP Code City Area Codes
Los Alamos County NM 87544 Los Alamos 505, 575
Los Alamos County NM 87545 Los Alamos 505
Los Alamos County NM 87547 White Rock 505

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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.