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 60403 Crest Hill Will County 779, 815
IL 60404 Shorewood Will County 779, 815
IL 60406 Blue Island Cook County 464, 708, 773, 872
IL 60407 Braceville Grundy County 779, 815
IL 60408 Braidwood Will County 779, 815
IL 60409 Calumet City Cook County 464, 708, 773, 872
IL 60410 Channahon Will County 779, 815
IL 60411 Chicago Heights Cook County 219, 464, 708
IL 60412 Chicago Heights Cook County 708
IL 60415 Chicago Ridge Cook County 464, 708
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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.