| Továrna na dokonalé programy, s.r.o. | Prague |
| Transferum.com | South Moravian |
| TranSoft a.s. | |
| TreeGrid | Prague |
| Tresoft, s.r.o. | Hradec Králové |
| Trezor company, s.r.o. | |
| TriloByte Statistical Software | Pardubice |
| Trinity Bank, a.s. | Prague |
| TRIONET | |
| Trisbee, s.r.o. | |
| Trisbee, s.r.o. | |
| Trivas Engineer s.r.o. | Central Bohemian |
| Trivi, a.s. | |
| Tropic Square, s.r.o. | |
| Trusted Solutions | Olomouc |
| TrustPort, a.s. | South Moravian |
| Tsbohemia.cz | Moravian-Silesian |
| TSE, spol. s r.o. | South Bohemian |
| TTC Holding, a.s. | Prague |
| TTC Telekomunikace, s.r.o. | Prague |
| Turris | |
| Twisto payments, a.s. | Prague |
| Ty-net, spol. s r.o. | Prague |
| Tyinternety.cz, s.r.o. | |
| UlovDomov.cz, s.r.o. | |
| Ultimate++ | Prague |
| UltimateSuite | |
| Unicode Systems, s.r.o. | |
| Unicorn University | |
| Unicorn, a.s. | Prague |
| UniCredit Bank Czech Republic and Slovakia, a.s. | Prague |
| UNIKUM Solutions, s.r.o. | |
| Unis computers, a.s. | Prague |
| Unismini - služby, spol. s r.o. | Prague |
| UNITES Systems, a.s. | |
| University of New York in Prague | Prague |
| University of Ostrava | |
| University of Ostrava - Department of Informatics and Computers | |
| University of Ostrava - Institute for Research and Applications of Fuzzy Modeling | Moravian-Silesian |
| Univerzita Hradec Králové | Hradec Králové |
| Univerzita J. E. Purkyně | |
| Univerzita Jana Amose Komenského Praha | |
| Univerzita Karlova | Prague |
| Univerzita Karlova - Katedra softwaru a výuky informatiky | |
| Univerzita Karlova v Praze - Centrum excelence - Institut teoretické informatiky | Prague |
| Univerzita Karlova v Praze - Katedra informačních technologií a technické výchovy | Prague |
| Univerzita Karlova v Praze - Katedra teoretické informatiky a matematické logiky | Prague |
| Univerzita obrany | |
| Univerzita Palackého v Olomouci | Olomouc |
| Univerzita Pardubice | |