Michigan Bell is the subsidiary of

AT&T AT&T Inc., an abbreviation for its predecessor's former name, the American Telephone and Telegraph Company, is an American multinational telecommunications holding company headquartered at Whitacre Tower in Downtown Dallas, Texas. It is the w ...

serving the state of

Michigan Michigan ( ) is a peninsular U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest, Upper Midwestern United States. It shares water and land boundaries with Minnesota to the northwest, Wisconsin to the west, ...

. Following the

Bell System divestiture The Bell System held a virtual monopoly over telephony infrastructure in the United States since the early 20th century until January 8, 1982. This divestiture of the Bell Operating Companies was initiated in 1974 when the United States Departm ...

on January 8, 1984, the company became a subsidiary of

Ameritech AT&T Teleholdings, Inc., formerly known as Ameritech Corporation (and, before that, American Information Technologies Corporation), was an American telecommunications company that arose out of the 1984 AT&T divestiture. Ameritech was one of the ...

, the

Regional Bell operating company A Regional Bell Operating Company (RBOC) was a corporate entity created as result of the antitrust lawsuit by the United States Department of Justice against the Western Electric Company and American Telephone and Telegraph Company (AT&T) in 194 ...

that served the

midwestern United States The Midwestern United States (also referred to as the Midwest, the Heartland or the American Midwest) is one of the four census regions defined by the United States Census Bureau. It occupies the northern central part of the United States. It ...

. Ameritech was subsequently acquired by SBC Communications, which later changed its name to

About

Michigan Bell was one of the 22

Local Exchange Carrier Local exchange carrier (LEC) is a regulatory term in telecommunications for the local telephone company. In the United States, wireline telephone companies are divided into two large categories: long-distance ( interexchange carrier, or IXCs) ...

s that were part of the original AT&T

Bell System The Bell System was a system of telecommunication companies, led by the Bell Telephone Company and later by the AT&T Corporation, American Telephone and Telegraph Company (AT&T), that dominated the telephone services industry in North America fo ...

until the 1984 divestiture, after which Michigan Bell and four other Midwestern telephone companies became part of Ameritech, the midwestern Regional Holding Company. Ameritech was one of the seven original Bell Regional Holding Companies, or "Baby Bells". By the early 1990s, Ameritech phased out state specific names such as Michigan Bell in favor of using the Ameritech name for marketing purposes. After Ameritech's acquisition by SBC Communications, the former Ameritech companies were briefly marketed as SBC Ameritech, as a transition to a unified "SBC" brand name in all 13 states in which SBC then did business. When this had been accomplished, in 2005, SBC Communications acquired AT&T. The newly merged company began marketing itself throughout the United States as the "new" AT&T. Michigan Bell is still the legal entity that provides telecommunications services in Michigan under the AT&T name. It is headquartered in Detroit. AT&T subsidiaries Bell System Companies based in Detroit American companies established in 1904 Telecommunications companies established in 1904 1904 establishments in Michigan {{US-telecom-company-stub