GTE Corporation, formerly General Telephone & Electronics Corporation (1955–1982), was the largest independent telephone company in the United States during the days of the Bell System. The company operated from 1926, with roots tracing further back than that, until 2000, when it was acquired by Bell Atlantic; the combined company took the name Verizon.
AT&T Teleholdings, Inc., formerly known as Ameritech Corporation, is an American telecommunications company that arose out of the 1984 AT&T divestiture. Ameritech was one of the seven Regional Bell Operating Companies that was created following the breakup of the Bell System. Ameritech was acquired in 1999 by SBC Communications, which subsequently acquired AT&T Corporation in 2006, becoming the present-day AT&T.
NYNEX Corporation was an American telephone company that served five states of New England as well as most of the state of New York from January 1, 1984 to August 14, 1997.
Pacific Telesis Group (PacTel) was one of the seven Regional Bell Operating Companies, sometimes also referred to as "RBOCs" or "Baby Bells", created in 1983 in preparation of the breakup of AT&T Corporation. Pacific Telesis was the holding company for Pacific Bell, Nevada Bell, Pacific Telesis International, PacTel Mobile Services and PacTel InfoSystems. Pacific Telesis was headquartered in San Francisco and incorporated in Nevada. It was acquired by SBC Communications in 1997, which would eventually become today’s AT&T Inc.
Altafiber, Inc., formerly Cincinnati Bell, is a regional telecommunications service provider based in Cincinnati, Ohio, United States. It provides landline telephone, fiber-optic Internet, and IPTV services through its subsidiaries Altafiber Home Phone and Hawaiian Telcom, which are the incumbent local exchange carriers for the Greater Cincinnati metropolitan area and Hawaii. Other subsidiaries provide enterprise information technology services and long distance calling.
Houston Cellular was a Houston-based cell phone company which provided AMPS and D-AMPS (TDMA) service in the Greater Houston area. It was formed in 1983 and was operated as a partnership between LIN Broadcasting Corp., Mobile Communication Corp. of America and BellSouth Co. Its headquarters were located in Houston, Texas.
The breakup of the Bell System was mandated on January 8, 1982, by a consent decree providing that AT&T Corporation would, as had been initially proposed by AT&T, relinquish control of the Bell Operating Companies, which had provided local telephone service in the United States. This effectively took the monopoly that was the Bell System and split it into entirely separate companies that would continue to provide telephone service. AT&T would continue to be a provider of long-distance service, while the now-independent Regional Bell Operating Companies (RBOCs), nicknamed the "Baby Bells", would provide local service, and would no longer be directly supplied with equipment from AT&T subsidiary Western Electric.
Verizon New York, Inc., formerly The New York Telephone Company (NYTel), was organized in 1896, taking over the New York City operations of the American Bell Telephone Company.
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, which 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.
Verizon New England, Inc. was a Bell Operating Company that once covered most of New England but most recently only served most of Massachusetts and all of Rhode Island. It was formerly New England Telephone and Telegraph Company, more commonly known as New England Telephone, which for seven decades served most of the New England area of the United States as a part of the original AT&T. New England Telephone's original coverage area included Maine, New Hampshire, and Vermont as well as Massachusetts and Rhode Island, Verizon has sold off service in the northern three states, which as of 2020 were served by Consolidated Communications.
Illinois Bell Telephone Company, LLC is the Bell Operating Company serving Illinois. It is owned by AT&T through AT&T Teleholdings, formerly Ameritech.
Qwest Corporation is a Regional Bell Operating Company owned by Lumen Technologies. It was formerly named U S WEST Communications, Inc. from 1991 to 2000, and also formerly named Mountain States Telephone and Telegraph Company, known as Mountain Bell from 1911 to 1991. It includes the former operations of Malheur Bell, Northwestern Bell and Pacific Northwest Bell as well.
SBC Long Distance LLC is a long-distance telephone company owned by AT&T that does business as AT&T Long Distance. SBC Long Distance competes with other long-distance providers who provide service within some of the Bell Operating Company service boundaries of AT&T. SBC Long Distance is a separate subsidiary than AT&T Communications, the incumbent long-distance carrier for most of the country acquired in the SBC merger with AT&T.
Dex One Corporation was an American marketing company providing online, mobile and print search marketing via their DexKnows.com website, print yellow pages directories and pay-per-click ad networks in the U.S.
Advanced Mobile Phone Service, Inc. was a subsidiary of AT&T prior to the Bell System Divestiture. Abbreviated AMPS, the company was created in 1978 to build and operate the new Advanced Mobile Phone System, also abbreviated AMPS. AMPS was developed by Bell Labs to replace older, severely limited radiophone services, such as IMTS. AMPS was one of the first modern cellular phone systems, which remained in operation until 2008.
Qwest Communications International, Inc. was a United States telecommunications carrier. Qwest provided local service in 14 western and midwestern U.S. states: Arizona, Colorado, Idaho, Iowa, Minnesota, Montana, Nebraska, New Mexico, North Dakota, Oregon, South Dakota, Texas, Utah, Washington, and Wyoming.
The Bell System was a system of telecommunication companies, led by the Bell Telephone Company and later by the American Telephone and Telegraph Company (AT&T), that dominated the telephone services industry in North America for over 100 years from its creation in 1877 until its antitrust breakup in 1983. The system of companies was often colloquially called Ma Bell, as it held a vertical monopoly over telecommunication products and services in most areas of the United States and Canada. At the time of the breakup of the Bell System in the early 1980s, it had assets of $150 billion and employed over one million people.
AT&T Corporation, commonly referred to as AT&T, an abbreviation for its former name, the American Telephone and Telegraph Company, was an American telecommunications company that provided voice, video, data, and Internet telecommunications and professional services to businesses, consumers, and government agencies.
The Southern New England Telephone Company, doing business as Frontier Communications of Connecticut, is a local exchange carrier owned by Frontier Communications.
