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
All states and U.S. territories
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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 60634 Chicago Cook County 224, 464, 708, 773, 847, 872
IL 60636 Chicago Cook County 773, 872
IL 60637 Chicago Cook County 773, 872
IL 60638 Chicago Cook County 464, 708, 773, 872
IL 60639 Chicago Cook County 464, 708, 773, 872
IL 60640 Chicago Cook County 773, 872
IL 60641 Chicago Cook County 773, 872
IL 60642 Chicago Cook County 312, 773, 872
IL 60643 Chicago Cook County 464, 708, 773, 872
IL 60644 Chicago Cook County 464, 708, 773, 872
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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.