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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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Union County ZIP Codes

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

County State ZIP Code City Area Codes
Union County NJ 07902 Summit 908
Union County NJ 07922 Berkeley Heights 862, 908, 973
Union County NJ 07974 New Providence 862, 908, 973
Union County NM 88410 Amistad 575, 806
Union County NM 88414 Capulin 575
Union County NM 88415 Clayton 575, 580, 806
Union County NM 88418 Des Moines 575
Union County NM 88419 Folsom 575, 580, 719
Union County NM 88422 Gladstone 575
Union County NM 88424 Grenville 575
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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.