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 62204 East Saint Louis St. Clair County 618
IL 62205 East Saint Louis St. Clair County 618
IL 62206 East Saint Louis St. Clair County 314, 557, 618
IL 62207 East Saint Louis St. Clair County 618
IL 62208 Fairview Heights St. Clair County 618
IL 62214 Addieville Washington County 618
IL 62215 Albers Clinton County 618
IL 62216 Aviston Clinton County 618
IL 62217 Baldwin Randolph County 618
IL 62218 Bartelso Clinton County 618
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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.