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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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Knox County ZIP Codes

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

County State ZIP Code City Area Codes
Knox County ME 04859 Spruce Head 207
Knox County ME 04860 Tenants Harbor 207
Knox County ME 04861 Thomaston 207
Knox County ME 04862 Union 207
Knox County ME 04863 Vinalhaven 207
Knox County ME 04864 Warren 207
Knox County ME 04865 West Rockport 207
Knox County MO 63446 Knox City 573, 660
Knox County MO 63458 Newark 573, 660
Knox County MO 63460 Novelty 660
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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.