| Asomatic AG | Lucerne |
| Aspaara | Zurich |
| Aspectra AG | Zurich |
| Aspivix S.A. | |
| Assiomatica AG | Zurich |
| Astrocast S.A. | Vaud |
| AtelArt Informatique | Valais |
| Atelier Design of Mars | Geneva |
| Ateliers de la Ville de Renens | |
| Aterios GmbH | Zug |
| atHeart Medical | |
| Athebio | |
| Atlantic Ventures GmbH | Zurich |
| Atopia Therapeutics | |
| Atpar AG | |
| Atrinum Ventures AG | |
| Attolight AG | |
| Aurealis Therapeutics | |
| Aurora's Grid | |
| Autentica | Zug |
| Auterion AG | Zurich |
| Autexis Holding AG | Aargau |
| Authena | |
| Authress | |
| AutoForm Engineering GmbH | Zurich |
| Automation and Control Systems AG | St. Gallen |
| AV Alliance | |
| Ava AG | Zurich |
| Avado | Zug |
| Avallain AG | |
| Avaloq Evolution AG | Zurich |
| Avantec AG | Zurich |
| AVAtronics S.A. | |
| Aveniq AG | Aargau |
| AVIK Systems | |
| Avintis S.A. | Fribourg |
| Avodata AG | Zurich |
| Avrion Therapeutics S.A. | |
| Avrios International AG | |
| AWARDIC GmbH | St. Gallen |
| AWK Group S.A. | Zurich |
| Axalbion S.A. | |
| Axeba AG | Zurich |
| Axeon | Solothurn |
| Axianet.ch S.à.r.l. | Valais |
| Aximetria GmbH | |
| Axino Solutions AG | |
| Axxiome | |
| Azone | Zurich |
| b-rayZ AG | |