Area code 810

Area code 810 is a telephone area code serving East Central Michigan. It includes the main cities of Flint, Lapeer, Port Huron, and all surrounding areas within The Thumb region of Michigan. More generally, it includes all of Genesee County and Lapeer County, and parts of Oakland County, Macomb County, St. Clair County, Sanilac County and Livingston County.

Selected areas in north Oakland County areas of Oxford, Addison, Brandon, Groveland, and Holly are also partially served by 810.

Area code 810 was implemented on December 1, 1993, and was Michigan's first new area code since 1961. It originally served all communities north of Wayne County that were part of area code 313, including the northern suburbs of Detroit.

Only four years later, Oakland County was split off as area code 248. This led to a situation in which residents of southwest Macomb County could leave their area code area by traveling one or two miles westwards, but reenter it by continuing west for another 30 miles.

In 2001, when area code 586, including most of Macomb County, was split off from 810, only the northern communities of Macomb and Oakland counties remained served by 810.

The 810 area code was one of three US regional area codes for the former AT&T TWX (TeletypeWriter eXchange) network, sold to Western Union in 1969 and renamed as Telex II. It covered Michigan, Ohio, Indiana and the US South (NC SC GA FL LA MS FL AL KY).

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