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.

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Warren County ZIP Codes

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

County State ZIP Code City Area Codes
Warren County NJ 07820 Allamuchy 908
Warren County NJ 07823 Belvidere 272, 484, 570, 610, 835, 908
Warren County NJ 07825 Blairstown 272, 570, 862, 908, 973
Warren County NJ 07829 Buttzville 908
Warren County NJ 07831 Changewater 908
Warren County NJ 07832 Columbia 272, 484, 570, 610, 835, 908
Warren County NJ 07833 Delaware 272, 570, 908
Warren County NJ 07838 Great Meadows 908
Warren County NJ 07840 Hackettstown 862, 908, 973
Warren County NJ 07844 Hope 908
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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.