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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 IL 61467 Oneida 309
Knox County IL 61472 Rio 309
Knox County IL 61474 Saint Augustine 309
Knox County IL 61485 Victoria 309
Knox County IL 61488 Wataga 309
Knox County IL 61489 Williamsfield 309
Knox County IL 61572 Yates City 309
Knox County IN 47512 Bicknell 812, 930
Knox County IN 47516 Bruceville 812, 930
Knox County IN 47524 Decker 812, 930
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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.