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
Maps and coordinates
County directory

St. Clair County ZIP Codes

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

County State ZIP Code City Area Codes
St. Clair County MI 48027 Goodells 586, 810
St. Clair County MI 48028 Harsens Island 226, 519, 548, 810
St. Clair County MI 48032 Jeddo 810
St. Clair County MI 48039 Marine City 226, 519, 548, 586, 810
St. Clair County MI 48040 Marysville 226, 519, 548, 810
St. Clair County MI 48041 Memphis 586, 810
St. Clair County MI 48049 North Street 810
St. Clair County MI 48054 East China 226, 519, 548, 586, 810
St. Clair County MI 48059 Fort Gratiot 810
St. Clair County MI 48060 Port Huron 226, 519, 548, 810
Page 6 of 8

Geographic Map of St. Clair County

Postal context

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.