| Technologické centrum AV ČR | Prague |
| Technosoft, spol. s r.o. | |
| Technoton Engineering | |
| TechProg, s.r.o. | |
| TechSoft Engineering, spol. s r.o. | |
| TELE3 | Prague |
| TELESIS Technologies, s.r.o. | Prague |
| Telmo, spol. s.r.o. | Prague |
| TelPro, spol. s r.o. | |
| Tenzor hosting | Prague |
| Terasoft, a.s. | |
| TERRA computer systems | South Moravian |
| TERSYS, s.r.o. | |
| Tescan Group, a.s. | |
| Tescan Group, a.s. | |
| TESCO SW, a.s. | Olomouc |
| TeskaLabs Ltd | |
| Textie | |
| TH Soft, s.r.o. | Pardubice |
| The Booster Labs, s.r.o. | |
| The Cave | Prague |
| Thein Digital, s.r.o. | |
| Think Easy, s.r.o. | |
| THINline, s.r.o. | Prague |
| Tibo Software | Pardubice |
| Tilia Impact Ventures | |
| Tiscali.cz | Prague |
| TKK-HIG, s.r.o. | |
| TKR Jašek, s.r.o. | |
| TMetric | |
| Tolgee, s.r.o. | |
| Tom Atom, s.r.o. | |
| Top Digital Group, s.r.o. | |
| TOP TECH, s.r.o. | Hradec Králové |
| TopMonks, s.r.o. | |
| TOPOL.io | |
| TopTech Brno, spol. s r.o. | |
| Továrna na dokonalé programy, s.r.o. | Prague |
| Transferum.com | South Moravian |
| TranSoft a.s. | |
| TRAU | |
| TreeGrid | Prague |
| Tresoft, s.r.o. | Hradec Králové |
| Trezor company, s.r.o. | |
| TriloByte Statistical Software | Pardubice |
| TRIONET | |
| Trisbee, s.r.o. | |
| Trivas Engineer s.r.o. | Central Bohemian |
| Trivi, a.s. | |
| Tropic Square, s.r.o. | |