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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 NM 88436 Sedan 575, 806
Union County OH 43007 Broadway 326, 937
Union County OH 43036 Magnetic Springs 326, 937
Union County OH 43040 Marysville 220, 326, 380, 614, 740, 937
Union County OH 43041 Marysville 937
Union County OH 43045 Milford Center 326, 380, 614, 937
Union County OH 43064 Plain City 220, 326, 380, 614, 740, 937
Union County OH 43067 Raymond 220, 326, 740, 937
Union County OH 43077 Unionville Center 380, 614
Union County OH 43344 Richwood 220, 326, 740, 937
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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.