Main companies
Telekom Deutschland | Electronic Beats | Hrvatski Telekom (Crnogorski Telekom (76.53%)) | HT Mostar (39.1%) | Magyar Telekom | Makedonski Telekom | OTE (40%) | Slovak Telekom | BT Group (12%) | Magenta Telekom
Main services
Magenta TV | Telekom Web&Mobile TV | T-Home | T-Mobile | T-Online | T-Systems | TVision (United States)
Mobile networks
Telekom: Croatia | Germany (Congstar) | Hungary | Montenegro | North Macedonia | Slovakia
T-Mobile: Czech Republic | Poland | Puerto Rico | United States | Metro by T-Mobile (United States)
Television channels (via OTE)
Cosmote Cinema | Cosmote Sport
Other brands
Austria: Magenta
Greece (via OTE): Cosmote (TV) | Frog Mobile
Romania: Combridge
United Kingdom: EE (via BT Group)2
United States: Mint Mobile | Ultra Mobile
Absorbed companies
MobileStar | Omnipoint Communications | Powertel | SunCom | VoiceStream Wireless | Western Wireless Corporation | UPC Austria | Layer3 TV | Sprint | UScellular
Former brands
T-Basis | T-BasisNet | T-Card | T-MobilNet | T-Net | T-Profi | T-ProfiNet | T-SystemNet
Germany: Joyn
Romania: Telekom Romania Mobile Communications8 (Cartela Telekom | MTV Mobile | MyAccount) | Dolce | Joyn | Telekom TV7 | Zapp | Frog Mobile | Cosmote MyTab
Bulgaria: Globul | Frog Mobile
Hungary: T-Mobile | Westel 0660
Former subsidiaries
United Kingdom: T-Mobile UK2 | Bulgaria: Globul3 | North Macedonia: Cosmofon4 | Albania: Telekom Albania5 | Philippines: Islacom6 | Romania: Telekom Romania (Telekom Sport7 (1 | 2 | 3 | 4 | 5 | 6) | Telekom Info7) (54% via OTE)7 | Netherlands: T-Mobile Nederland1 (Ben, Tele2) | MTV Mobile9 | Poland: MTV Mobile10
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