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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 60073 Round Lake 224, 779, 815, 847
Lake County IL 60075 Russell 224, 262, 847
Lake County IL 60079 Waukegan 224
Lake County IL 60083 Wadsworth 224, 847
Lake County IL 60084 Wauconda 224, 779, 815, 847
Lake County IL 60085 Waukegan 224, 847
Lake County IL 60086 North Chicago 224
Lake County IL 60087 Waukegan 224, 847
Lake County IL 60088 Great Lakes 224, 847
Lake County IL 60089 Buffalo Grove 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.