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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 GA 31620 Adel 229
Cook County GA 31627 Cecil 229
Cook County GA 31637 Lenox 229
Cook County GA 31647 Sparks 229
Cook County IL 60004 Arlington Heights 224, 847
Cook County IL 60005 Arlington Heights 224, 847
Cook County IL 60006 Arlington Heights 224
Cook County IL 60007 Elk Grove Village 224, 331, 630, 847
Cook County IL 60008 Rolling Meadows 224, 847
Cook County IL 60009 Elk Grove Village 224
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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.