Southwestern Bell Mobile Systems, Inc. was a wireless telephone company. It was created in 1984 as a split-off of

Advanced Mobile Phone Service 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 develop ...

, the original wireless subsidiary of the

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 ...

. It was a division of

Southwestern Bell Corporation 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 ...

. It continued to operate as Southwestern Bell Mobile Systems until 2000, when

SBC Communications 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 ...

and

BellSouth BellSouth, LLC (stylized as ''BELLSOUTH'' and formerly known as BellSouth Corporation) was an American telecommunications holding company based in Atlanta, Georgia. BellSouth was one of the seven original Regional Bell Operating Companies after ...

combined their wireless operations into a single company,

Cingular Wireless AT&T Mobility, LLC, also known as AT&T Wireless and marketed as simply AT&T, is an American telecommunications company. Formed in April 2000 as Cingular Wireless LLC, It is a wholly owned subsidiary of AT&T Inc. and provides wireless serv ...

. Southwestern Bell Mobile Systems' assets were then transferred to a Cingular as a

limited liability company A limited liability company (LLC) is the United States-specific form of a private limited company. It is a business structure that can combine the pass-through taxation of a partnership or sole proprietorship with the limited liability of ...

named Cingular Southwestern Bell Mobile Systems, LLC. The company existed until 2006 when it was dissolved.Missouri Secretary of State, Filed Documents for Cingular Southwestern Bell Mobile Systems, LLC
/ref> Southwestern Bell Mobile Systems' physical assets survive in what is now

AT&T Mobility AT&T Mobility, LLC, also known as AT&T Wireless and Trade name, marketed as simply AT&T, is an American telecommunications company. Formed in April 2000 as Cingular Wireless LLC, It is a wholly owned subsidiary of AT&T, AT&T Inc. and provide ...

References

{{AT&T AT&T subsidiaries Defunct mobile phone companies of the United States Defunct telecommunications companies of the United States American companies established in 1983 Telecommunications companies established in 1983 Telecommunications companies disestablished in 2006 American companies disestablished in 2006