| AceCardGames | North Holland |
| Acerta Pharma B.V. | |
| Aces Direct B.V. | North Brabant |
| ACES International | Gelderland |
| Aces IT Consultancy & Services | North Brabant |
| AceView | North Brabant |
| ACI B.V. | North Brabant |
| ACI Computers | Friesland |
| ACKspace | |
| AcQ International | North Brabant |
| Acqda | Utrecht |
| Acrobator Ventures | |
| Acrux Software | North Holland |
| ACS Biomarker B.V. | |
| ACT Venture Partners | North Holland |
| Actief Software | South Holland |
| Actilus | North Brabant |
| Actis Business Partners | North Holland |
| Active Info | Utrecht |
| Active Professionals | South Holland |
| ActiveView | South Holland |
| ActiveXperts Software B.V. | Overijssel |
| Activium | Gelderland |
| Activo Groep B.V. | South Holland |
| Acuity | North Brabant |
| Acute Studio | |
| ACW-IT | |
| AD Hosting B.V. | Gelderland |
| Adams Multilingual Recruitment | North Holland |
| AdBirds | North Holland |
| Added Value Electronics | South Holland |
| AddOptics Operations B.V. | |
| Adecs Airinfra | South Holland |
| Adfocom | South Holland |
| Adfontes Software B.V. | |
| Admicom Systems | Utrecht |
| Admire Webdesign | Overijssel |
| Adnetcom NetHosting | North Holland |
| Adobe Netherlands | North Holland |
| Adsby B.V. | |
| Adsolutions | North Holland |
| Advanced Encryption Technology Europe B.V. | Gelderland |
| Advanced Programs | Utrecht |
| Advanced Team Systems Center B.V. | North Brabant |
| Advantech Europe | North Brabant |
| Advice Robo | |
| AdviceRobo | South Holland |
| Advidi | |
| Advisie | Utrecht |
| ADX-Europe B.V. | Overijssel |