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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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Lake County ZIP Codes

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

County State ZIP Code City Area Codes
Lake County IL 60002 Antioch 224, 262, 779, 815, 847
Lake County IL 60010 Barrington 224, 847
Lake County IL 60015 Deerfield 224, 847
Lake County IL 60020 Fox Lake 224, 779, 815, 847
Lake County IL 60030 Grayslake 224, 847
Lake County IL 60031 Gurnee 224, 847
Lake County IL 60035 Highland Park 224, 847
Lake County IL 60037 Fort Sheridan 224, 847
Lake County IL 60040 Highwood 224, 847
Lake County IL 60041 Ingleside 224, 779, 815, 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.