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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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Hardin County ZIP Codes

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

County State ZIP Code City Area Codes
Hardin County KY 42776 Sonora 270, 364
Hardin County KY 42784 Upton 270, 364
Hardin County KY 42788 White Mills 270, 364
Hardin County OH 43326 Kenton 220, 326, 419, 567, 740, 937
Hardin County OH 43340 Mount Victory 220, 326, 419, 567, 740, 937
Hardin County OH 43345 Ridgeway 326, 937
Hardin County OH 43346 Roundhead 326, 419, 567, 937
Hardin County OH 45810 Ada 419, 567
Hardin County OH 45812 Alger 419, 567
Hardin County OH 45835 Dola 419, 567
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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.