| Taxan | United States | July 1981 | — | 2 |
| TDK | Japan | December 7, 1935 | — | 1 |
| TDK Recording Media Europe, S.A. | Luxembourg | — | — | 1 |
| Tea Monster Games | Canada | — | 1 | 1 |
| Team ADOM | Germany | 2019 | 1 | — |
| Team GrisGris | Japan | 1998 | 2 | — |
| Team Hoi | Netherlands | 1988 | 8 | — |
| Team KwaKwa | Switzerland | — | 1 | — |
| Team Ladybug | Japan | — | 1 | — |
| Team Meat | United States | — | 1 | 1 |
| Team Ninja | Japan | 1995 | 51 | — |
| Team Reptile | Netherlands | September 2011 | 2 | 2 |
| Team Salvato | United States | 2017 | 1 | — |
| Team Silent | Japan | 1997 | 3 | — |
| Team Soda | People's Republic of China | — | 1 | — |
| Team Soho | United Kingdom | 1994 | 2 | — |
| Team SolEtude | Italy | — | 2 | 2 |
| Team WIBY | Australia | 2018 | 1 | — |
| Team17 | United Kingdom | December 1990 | 39 | 53 |
| Team6 Game Studios | Netherlands | 2001 | 6 | — |
| TeamKill Media | United States | 2016 | 1 | 1 |
| Tech Arts Inc. | Japan | October 1996 | 1 | 2 |
| Technical Education Research Centers | United States | 1965 | 1 | — |
| Technical Group Laboratory | Japan | July 1984 | — | 3 |
| Techno-Top | Japan | May 1999 | 1 | 1 |
| TechnoBrain | Japan | January 13, 1994 | 1 | 1 |
| Technosoft | Japan | February 1980 | 6 | 4 |
| Technōs Japan | Japan | December 1981 | 16 | 13 |
| Tecmo | Japan | July 31, 1967 | 33 | 45 |
| Tectoy | Brazil | 1987 | 6 | 6 |
| Teggno Interactive | Brazil | 2021 | 1 | — |
| Teknopiste | Finland | 1969 | — | — |
| Telegames | United States | — | 1 | 3 |
| Telenet Japan | Japan | 1983 | 7 | 6 |
| Telltale Games | United States | July 2004 | 39 | 22 |
| Telstar Electronic Studios | United Kingdom | 1993 | — | 1 |
| Templar Studios | United States | 1997 | 1 | — |
| Tencent | People's Republic of China | November 12, 1998 | — | 6 |
| Tencent Games | People's Republic of China | 2003 | 1 | 5 |
| Tender Claws | United States | 2014 | 3 | 4 |
| Tengen | United States | 1987 | 2 | 6 |
| TENKY | Japan | December 14, 1989 | 1 | — |
| Tequila Mobile | Poland | December 27, 2007 | 1 | 1 |
| Teravision Games | Colombia | — | 1 | — |
| Terminal Reality | United States | 1994 | 8 | — |
| Terraglyph Interactive Studios | United States | 1994 | 1 | — |
| Terrible Posture Games | United States | — | 4 | 4 |
| Terrible Toybox | United States | December 2, 2015 | — | 1 |
| Terzio Verlag | Germany | 1997 | — | 7 |
| Tessera Studios | Spain | 2017 | 2 | — |
| Texelworks | Romania | — | 1 | — |
| Tha Ltd. | Japan | — | 1 | — |
| Thalamus Ltd | United Kingdom | 1986 | — | 2 |
| Thalion Software | Germany | 1988 | 7 | 10 |
| That Silly Studio | United Kingdom | December 7, 2016 | 1 | — |
| The 3DO Company | United States | September 12, 1991 | 8 | 25 |
| The Adventure Company | Canada | 2002 | — | 12 |
| The Adventure Workshop | United Kingdom | 1992 | — | 1 |
| The Arcade Crew | France | 2018 | — | 3 |
| The Assembly Line | United Kingdom | 1989 | 1 | — |
| The Behemoth | United States | 2003 | 3 | 2 |
| The Bergson's Games Studios | Brazil | — | 1 | 1 |
| The Bitmap Brothers | United Kingdom | 1987 | 3 | — |
| The Chinese Room | United Kingdom | 2007 | 2 | — |
| The Coalition | Canada | February 2010 | 5 | — |
| The Code Monkeys | United Kingdom | 1988 | 2 | — |
| The Dairymen | United Kingdom | September 26, 2000 | — | 1 |
| The Digital Village | United Kingdom | 1994 | 1 | — |
| The Farm 51 | Poland | 2005 | 5 | 2 |
| The Fighter Collection | United Kingdom | — | — | 1 |
| The Game Bakers | France | August 18, 2010 | 1 | — |
| The Game Creators | United Kingdom | 1999 | — | — |
| The Game Designers Studio | Japan | June 22, 1999 | 1 | — |
| The Game Factory | Denmark | November 6, 1997 | — | 3 |
| The Gentlebros | Singapore | 2015 | 3 | 1 |
| The Iconfactory | United States | 1996 | 1 | — |
| The Initiative | United States | — | 1 | — |
| The Knights of Unity | Poland | 2015 | 1 | 2 |
| The Label | United States | 2016 | — | 2 |
| The Learning Company | United States | 1980 | 7 | 6 |
| The Lego Group | Denmark | 1932 | 2 | 15 |
| The Men Who Wear Many Hats | — | February 2012 | 1 | 1 |
| The MIX Games | United States | May 24, 2021 | — | 1 |
| The Molasses Flood | United States | November 5, 2014 | 1 | 1 |
| The New York Times | United States | September 18, 1851 | 1 | — |
| The New York Times Company | United States | September 18, 1851 | — | 1 |
| The Nuttery Entertainment | Sweden | 2016 | 1 | — |
| The Outer Zone | Denmark | — | 1 | — |
| The Parasight | Poland | — | 1 | — |
| The Pixel Hunt | France | January 24, 2014 | 2 | 1 |
| The Pokémon Company | Japan | April 23, 1998 | 5 | 40 |
| The Pokémon Company International | United States | — | 1 | — |
| The Quantum Astrophysicists Guild | United States | May 17, 2012 | 1 | 8 |
| The Sales Curve | United Kingdom | 1988 | — | 3 |
| The Sims Studio | United States | 2006 | 4 | — |
| The Software Toolworks | United States | 1980 | 2 | 2 |
| The Vision Factory | Netherlands | 1993 | 2 | — |
| The Walt Disney Company | United States | October 16, 1923 | — | 1 |
| The Walt Disney Company (Japan) | Japan | 1959 | 1 | — |
| Thermite Games | People's Republic of China | July 10, 2020 | — | 4 |