Ameritech Mobile Communications, LLC was the first company in the United States to provide cellular mobile phone service to the general public. Cell service became publicly available in Chicago on October 13, 1983. The company was a division of Ameritech which, as of January 1, 1984, was the holding company of Illinois Bell, Michigan Bell, Wisconsin Bell, Ohio Bell, and Indiana Bell, who provides landline service to the Great Lakes region. From around 1986, Cincinnati Bell held a 45% stake in the company. Originally named Ameritech Mobile Communications, it later became known as Ameritech Cellular.