Area code 810

Area code 810 was created on December 1, 1993, in a mid-eastern section of Michigan, when numbering plan area 313 in the southeaster part of the state was divided. A permissive dialing period ended on August 10, 1994 when both area codes could be dialed to reach destinations. The initial numbering plan area included the counties of Oakland, Macomb, Genesee, Lapeer, St. Clair, and Sanilac as well as small sections of Saginaw, Shiawassee, Livingston, Washtenaw, and Wayne counties north of Detroit. Most of Washtenaw County, all of Monroe County, and the southern and western portions of Wayne County (including the City of Detroit) remained in the 313 area code. The split created Michigan's first new area code since 1961, and permitted interchangeable central office codes. Within only a year of the split, demand for telephone numbers increased such that there were plans for a new area code. Ameritech once again applied to the North American Numbering Plan Administrator for additional relief. As a result, Oakland County received the new area code 248, with a start of permissive dialing on May 10, 1997.