| Active 24 s.r.o. | Prague |
| ACTIVE24, s.r.o. | Prague |
| Actnow Ventures | |
| ACTUAL NET marketing, s.r.o. | |
| AD Studio, s.r.o. | |
| Adam Technology | |
| Adaptic Innovation, a.s. | Prague |
| Adaptica, a.s. | Zlín |
| ADC Solution, s.r.o. | |
| Adeon CZ, s.r.o. | South Moravian |
| Admanet.cz | Prague |
| AdmWin | South Moravian |
| ADP CZ, a.s. | Prague |
| ADSL, s.r.o. | Prague |
| Advanced Technology Partners, s.r.o. | |
| Advanto Group, s.r.o. | |
| AeroHosting.cz | Zlín |
| Aerojobsinternational, s.r.o. | |
| Agionet, s.r.o. | |
| Ahasware, s.r.o. | |
| AI Roadmap Institute | Prague |
| AI Startup Incubator | Prague |
| AI-Tomatica | |
| AIffinity | |
| AIKEN, s.r.o. | Central Bohemian |
| AIMS API, s.r.o. | |
| AINEX účetní software | Olomouc |
| Airtime Pro | |
| AIS Software, a.s. | South Moravian |
| AISoft spol. s r.o. | |
| Aivision, s.r.o. | Prague |
| Akademie věd České republiky | |
| Akcelerátor VŠEM | |
| Akermann Electronic Praha, s.r.o. | Prague |
| AKSOS WebDesign | Prague |
| Akta.cz | South Moravian |
| Albatrosmedia, a.s. | |
| Alberon Letohrad s.r.o. | Pardubice |
| Alda Games, s.r.o. | |
| Alfabit, s.r.o. | |
| Alfatelecom, s.r.o. | Prague |
| ALIS spol. s.r.o. | Liberec |
| Alkalis | Ústí nad Labem |
| All-Computer.cz | |
| ALL.COM - software, s.r.o. | |
| Alliance Trade Group, s.r.o. | Prague |
| AllisNet, s.r.o. | |
| Allium, s.r.o. | South Moravian |
| Allstar Group, s.r.o. | Prague |
| Almara, s.r.o. | South Moravian |