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 60499 Bedford Park Cook County 464, 708
IL 60501 Summit Argo Cook County 464, 708, 773, 872
IL 60502 Aurora DuPage County 331, 630
IL 60503 Aurora Will County 331, 630
IL 60504 Aurora DuPage County 331, 630
IL 60505 Aurora Kane County 331, 630
IL 60506 Aurora Kane County 331, 630
IL 60507 Aurora Kane County 630
IL 60510 Batavia Kane County 331, 630
IL 60511 Big Rock Kane County 331, 630, 779, 815
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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.