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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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Dekalb County ZIP Codes

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

County State ZIP Code City Area Codes
DeKalb County IL 60111 Clare 779, 815
DeKalb County IL 60112 Cortland 779, 815
DeKalb County IL 60115 Dekalb 779, 815
DeKalb County IL 60129 Esmond 779, 815
DeKalb County IL 60135 Genoa 779, 815
DeKalb County IL 60145 Kingston 779, 815
DeKalb County IL 60146 Kirkland 779, 815
DeKalb County IL 60150 Malta 779, 815
DeKalb County IL 60178 Sycamore 224, 331, 630, 779, 815, 847
DeKalb County IL 60520 Hinckley 331, 630, 779, 815
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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.