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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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Cook County ZIP Codes

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

County State ZIP Code City Area Codes
Cook County IL 60043 Kenilworth 224, 847
Cook County IL 60053 Morton Grove 224, 847
Cook County IL 60055 Palatine 224
Cook County IL 60056 Mount Prospect 224, 847
Cook County IL 60062 Northbrook 224, 847
Cook County IL 60065 Northbrook 224
Cook County IL 60067 Palatine 224, 847
Cook County IL 60068 Park Ridge 224, 773, 847, 872
Cook County IL 60070 Prospect Heights 224, 847
Cook County IL 60074 Palatine 224, 847
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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.