U.S. postal lookup

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.

42,735 verified records
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State directory

Illinois ZIP Codes

Complete postal directory, details, and geographic map for the State of Illinois.

State ZIP Code City County Area Codes
IL 60086 North Chicago Lake County 224
IL 60087 Waukegan Lake County 224, 847
IL 60088 Great Lakes Lake County 224, 847
IL 60089 Buffalo Grove Lake County 224, 847
IL 60090 Wheeling Cook County 224, 847
IL 60091 Wilmette Cook County 224, 847
IL 60092 Libertyville Lake County 224
IL 60093 Winnetka Cook County 224, 847
IL 60094 Palatine Cook County 224
IL 60095 Palatine Cook County 847, 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.