| Publisher | Games | Geek | Avg |
| Tempo Games (II) | 1 | — | — |
| Tempo Games (III) | 1 | — | — |
| Tempus Fugit Games | 1 | — | — |
| Tenacious Games | 1 | — | — |
| TENKIGAMES | 7 | 5.59 | 5.77 |
| Tennent's Beer | 1 | — | — |
| Teorema | 2 | — | — |
| Teriyaki Games | 1 | — | — |
| Terra Lannoo | 1 | — | — |
| Terra Nova Games | 5 | 5.69 | 6.27 |
| Terra Publica | 2 | — | — |
| Terra Toys | 2 | — | — |
| Terran Games, Inc. | 2 | — | — |
| TerreDice Games | 1 | — | — |
| Terrible Games | 3 | — | — |
| Territoires d'Outre Mondes (TOM) | 1 | — | — |
| Terrorbull Games | 3 | — | — |
| Tesco | 6 | 5.49 | 5.18 |
| Tesla Games | 35 | 6.39 | 7.54 |
| Tessellation Games LLC | 2 | — | — |
| Tessera Games | 1 | — | — |
| Test of Battle Games | 1 | — | — |
| Test Video Game Company 2 | 1 | — | — |
| Tetrahedron Games | 2 | — | — |
| Tetrakis | 2 | — | — |
| Tettix Games | 2 | — | — |
| Tezuka Productions | 1 | — | — |
| TF Verlag UG | 4 | — | — |
| TF1 Games | 13 | 5.46 | 5.42 |
| TFL Spellen | 1 | — | — |
| TGG Games | 8 | 5.98 | 6.85 |
| TGM Editora | 5 | 5.54 | 7.05 |
| Th3rd World Studios (3WS Games) | 7 | 5.61 | 6.74 |
| Thames & Kosmos | 83 | 6.09 | 7.01 |
| Thane's Games | 1 | — | — |
| That's What She Said Inc. | 1 | — | — |
| The Aerie Games | 1 | — | — |
| The American Belt Company | 1 | — | — |
| The Art of War | 1 | — | — |
| The Avalon Hill Game Co | 240 | 5.74 | 6.33 |
| The Avalon Hill Intercontinental Kriegspiel Society | 1 | — | — |
| The Bodleian Library | 1 | — | — |
| The Bombay Company | 2 | — | — |
| The Boots Company, PLC | 3 | — | — |
| The Bored Game Company | 6 | 5.92 | 6.52 |
| The Brand Cafe, Inc. | 1 | — | — |
| The British Library | 1 | — | — |
| The British Museum | 1 | — | — |
| The Brothers Murph | 1 | — | — |
| The Cabinet of Curiosities | 1 | — | — |
| The Canadian Group | 8 | 5.36 | 5.42 |
| The Card Cabinet | 1 | — | — |
| The Center for the Gifted Child, Inc. | 1 | — | — |
| The City of Games | 7 | 6.29 | 7.39 |
| The Colonial Williamsburg Foundation | 1 | — | — |
| The Contender | 1 | — | — |
| The Creative Assembly | 1 | — | — |
| The Creativity Hub | 27 | 5.59 | 6.52 |
| The Cunning Artificer | 1 | — | — |
| The Daniel Zayas Company | 1 | — | — |
| The Dark Imp | 1 | — | — |
| The Darker Side Games | 1 | — | — |
| The Denver Dry Goods Co | 1 | — | — |
| The Detective Society | 1 | — | — |
| The Dietz Foundation | 7 | 5.57 | 7.19 |
| The Dusty Top Hat Ltd. | 3 | — | — |
| The Elephant Chess Club | 2 | — | — |
| The Embossing Company | 4 | — | — |
| The Emperor's Press | 2 | — | — |
| The Enigma Emporium | 1 | — | — |
| The Escape Game | 1 | — | — |
| The Everyday Game Company | 1 | — | — |
| The Finance Game Company | 1 | — | — |
| The Five of Us, Inc. | 1 | — | — |
| The Flaggs, Inc. | 1 | — | — |
| The Flux Capacity | 4 | — | — |
| The Flying Games | 17 | 5.63 | 6.46 |
| The Freaky 42 | 2 | — | — |
| The Fruckus Company | 2 | — | — |
| The Future Trends Experience, Ltd. | 1 | — | — |
| The Gadget Shop | 1 | — | — |
| The Game Builders | 8 | 5.92 | 6.94 |
| The Game Chef | 2 | — | — |
| The Game Crafter, LLC | 47 | 5.60 | 6.33 |
| The Game Dealers Ltd. | 1 | — | — |
| The Game Forger | 1 | — | — |
| The Game Gallery Works | 1 | — | — |
| The Game Keeper, Inc. | 1 | — | — |
| The Game Master BV | 29 | 6.03 | 6.34 |
| The Game Works, Inc. | 5 | 5.62 | 5.35 |
| The Gamers | 65 | 5.62 | 7.28 |
| The GamerSpark | 2 | — | — |
| The Games Gang, LTD | 12 | 5.61 | 5.69 |
| The Games Team Ltd. | 4 | — | — |
| The Garden Game, Ltd. | 1 | — | — |
| The Geeksmith CG | 1 | — | — |
| The Gelles-Widmer Division: McGraw-Hill Book Company, Inc. | 1 | — | — |
| The Giant Brain | 1 | — | — |
| the glyphpress | 1 | — | — |
| The Good Game Company | 5 | 5.51 | 5.96 |