Türk Telekom is the formerly state owned Turkish telecommunications company. Türk Telekom was being separated from the Post Office in 1995. In November 2005 it was privatized to Oger Telecom.

Turk Telekom group provides integrated telecommunication services from PSTN, GSM to wide band internet. Turk Telekom group companies have 16.8 million PSTN customers, 6 million ADSL customers and 12.1 million GSM customers as of September 30, 2009.^{[citation needed]} With its network substructure, covering the whole country, the group companies offer a wide range of services to personal and corporate customers. Turk Telekom, who is the owner of the 99,9% of shares of the companies TTNET, Argela, Innova, Sebit A.Ş. and AssisTT, is also the owner of 81% of the shares of Avea, which is one of the three GSM operators in Turkey. Turk Telekom also supports Albtelecom in Albania. The 55% of the shares of Turk Telekom belongs to Oger Telekomünikasyon A.Ş. and the 30% of the shares belongs to Undersecretariat of Treasure of Turkey. The remaining 15% of shares has been offered to public.