| Improvisio Software, s.r.o. | Prague |
| Impulse Ventures | |
| In creative | |
| Incomaker | Prague |
| inCUBE Interactive, s.r.o. | |
| Industra | |
| iNET Solutions, s.r.o. | Prague |
| Inexes, s.r.o. | Prague |
| Infocity Hosting | Moravian-Silesian |
| INFONIA spol. s r.o. | Prague |
| Informica | Prague |
| InfoTech-Cs | South Moravian |
| Ing. Ondřej Bým - ONIT | Liberec |
| Ing. Petr Falek, Engineering Service | South Bohemian |
| InstaCover | |
| Institute of Information Theory and Automation | Prague |
| Institute of Information Theory and Automation, Czech Academy of Sciences | |
| Institute of Mathematics of the Czech Academy of Sciences | Prague |
| Institute of Scientific Instruments of the Czech Academy of Sciences | |
| Integsoft, s.r.o. | |
| INTELEK.CZ, s.r.o. | |
| Intelligent Trading Foundation | |
| Intencio, s.r.o. | South Moravian |
| Intercodec Czech, s.r.o. | |
| InterEco services, s.r.o. | |
| International Business Forum | |
| Internet Info, s.r.o. | |
| Internet Pb, spol. s r.o. | Prague |
| Internet Projekt, s.r.o. | Prague |
| Internethome, s.r.o. | Moravian-Silesian |
| INTERNEXT 2000, s.r.o. | Zlín |
| INTERSOFT - Automation, s.r.o. | |
| Inven Capital | |
| Inventive Software, s.r.o. | Prague |
| Investování na Fundliftu | |
| Invia.cz, a.s. | |
| iolevel, s.r.o. | |
| iotaCSS | Prague |
| IPEX | Prague |
| iPhoneDoktor.cz | Prague |
| iPhoneServis.cz | Prague |
| Ipos-Soft, spol. s r.o. | |
| IQE Europe | |
| IR-webdesign | South Moravian |
| IT Partner | Hradec Králové |
| IT Signet, s.r.o. | Prague |
| IT-Help | |
| ITACA Business Incubator | Prague |
| itDesign | Plzeň |
| iTech21, s.r.o. | |