| Alquist AI | |
| Altairis, s.r.o. | South Moravian |
| Altap Salamander | Liberec |
| ALTCHA | |
| ALTER, s.r.o. | Plzeň |
| Altix, s.r.o. | Zlín |
| Altsoft | Karlovy Vary |
| Alwil Trade, spol. s r.o. | Prague |
| Alza.cz, a.s. | |
| AMBIS vysoká škola, a.s. | |
| Amenit s.r.o. | Moravian-Silesian |
| AMgrade | |
| Ami Praha, a.s. | Prague |
| Amio | |
| Amos Software, spol. s r.o. | |
| Amotiq | |
| Andrej Gajdos | |
| ANECT, a.s. | Prague |
| ANeT-Advanced Network Technology, s.r.o. | South Moravian |
| ANETE, spol. s r.o. | |
| Anglo American University | |
| Annex NET, s.r.o. | |
| ANT studio, s.r.o. | |
| Antema | Liberec |
| Antonín Daněk | Prague |
| Apify | |
| Apigenix, s.r.o. | |
| Apollo Multimedia, s.r.o. | Prague |
| Apollo Soft Ltd | |
| Appfyl | |
| Appio | |
| Applic, s.r.o. | Liberec |
| Applifting, s.r.o. | Prague |
| AppSatori, s.r.o. | |
| Appteria | |
| AQUA, a.s. | |
| Aquila TS, s.r.o. | Pardubice |
| ARBES Technologies, a.s. | Prague |
| ARBO Technologies, s.r.o. | |
| ARC-Robotics, s.r.o. | |
| Arcdata Praha, s.r.o. | |
| ARCH LAB, s.r.o. | Olomouc |
| Arelion | |
| ARET Praha, s.r.o. | Prague |
| ARGO22, s.r.o. | |
| ART Data s.r.o. | South Moravian |
| ArtFocus | Prague |
| Artic Studio | Central Bohemian |
| Artiffine | |
| ARTIN, spol. s r.o. | South Moravian |