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.

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Madison County ZIP Codes

Browse all ZIP Codes, cities, and associated area codes registered in Madison County.

County State ZIP Code City Area Codes
Madison County IL 62018 Cottage Hills 618
Madison County IL 62021 Dorsey 618
Madison County IL 62024 East Alton 618
Madison County IL 62025 Edwardsville 618
Madison County IL 62026 Edwardsville 618
Madison County IL 62034 Glen Carbon 618
Madison County IL 62035 Godfrey 618, 636
Madison County IL 62040 Granite City 618
Madison County IL 62046 Hamel 618
Madison County IL 62048 Hartford 314, 557, 618, 636
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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.