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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 PA 17837 Lewisburg 272, 570
Union County PA 17844 Mifflinburg 272, 570, 582, 814
Union County PA 17845 Millmont 223, 272, 570, 582, 717, 814
Union County PA 17855 New Berlin 272, 570
Union County PA 17856 New Columbia 272, 570
Union County PA 17880 Swengel 272, 570
Union County PA 17883 Vicksburg 570
Union County PA 17885 Weikert 223, 272, 570, 582, 717, 814
Union County PA 17886 West Milton 272, 570
Union County PA 17887 White Deer 272, 570
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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.