| Fragaria, s.r.o. | Prague |
| Fram Software, s.r.o. | Prague |
| FreeHosting | Prague |
| FULLCOM systems, s.r.o. | |
| FutLab.cc | |
| Future Port Prague | Prague |
| Futured | South Moravian |
| G.L.Electronic, s.r.o. | |
| Galance.NET | Central Bohemian |
| GC System | South Moravian |
| GDI, s.r.o. | South Moravian |
| GEDIP | Zlín |
| Geetoo Holding, a.s. | Prague |
| Geewa, a.s. | Prague |
| GeneProof, a.s. | |
| General AI Challenge | Prague |
| General Bytes, s.r.o. | |
| Genesis Capital, s.r.o. | Prague |
| Gentleface, s.r.o. | Prague |
| GEPRO, spol. s r.o. | Prague |
| GES-ELECTRONICS, a.s. | Plzeň |
| GESTO Computers, spol. s r.o. | Prague |
| Giant interactive, s.r.o. | Prague |
| Gigaweb | Hradec Králové |
| GINA Software, s.r.o. | |
| Gisat, s.r.o. | |
| GISoft | Moravian-Silesian |
| GiTy, a.s. | South Moravian |
| GLOBDATA, a.s. | |
| Globula | |
| Glueo, s.r.o. | Prague |
| Gona System CZ, s.r.o. | |
| goNET, s.r.o. | |
| Good Sailors, s.r.o. | Ústí nad Labem |
| GoodAI | Prague |
| Gospace Labs, s.r.o. | |
| Gransy s.r.o. | Prague |
| Graweb, s.r.o. | |
| Greg Berry Studio | Prague |
| Greg Computers, s.r.o. | Prague |
| Greycortex, s.r.o. | |
| GreyCortex, s.r.o. | |
| Gringo | Prague |
| Grouport | |
| GS B2B, s.r.o. | Prague |
| GTM Plus | |
| Guardant | Prague |
| H1.cz | Prague |
| ha-vel internet, s.r.o. | Moravian-Silesian |
| Hackerspace Prague [brmlab] | Prague |