One of the top US phone companies without a connection to what used to be Ma Bell, Telephone and Data Systems (TDS) has about 6.1 million local phone and wireless customers in 34 states. The company's core business unit,  U.S. Cellular, serves about 4.9 million customers in 23 states; key markets are in the central and mid-Atlantic regions. The company also offers fixed-line and broadband Internet services in rural and suburban markets in 36 states through its  TDS Telecom subsidiary, which provides local service to 1.2 million access lines through more than 110 incumbent local-exchange carriers (ILEC). Data networking and hosted telecom services are provided to business clients through the TDS Business unit.