Southwestern Bell Telephone Company, or SBC for short, is an AT&T wholly-owned subsidiary. AT&T is an Internet Services firm that also offers an email service through SBCglobal, which was previously known as SBC Internet Services because it exclusively offers internet access. SBC's headquarters are located at One AT&T Plaza in Dallas, Texas. In its operation territory and parts of Illinois, SBC also does business in a similar manner as other DBA (Business Name). SBC's email services are provided to its customers through a partnership with AT&T and Yahoo. SBCglobal email is a new package that allows SBC consumers access to all portions of Yahoo. SBCglobal email login also offers SBC Internet, which is widely regarded as the country's best and most accessible service provider.