| ADTelecom | Barcelona |
| Adur Software Productions | Gipuzkoa |
| Advanced Brain Companion Diagnostics Spain, S.L. | Barcelona |
| Advanced Computer Trading, S.L. | Madrid |
| Advanced Medialabs, S.L. | Madrid |
| Advanced Software Production Line, S.L. | Madrid |
| Advancing | Barcelona |
| Advantic Sistemas y Servicios, S.L. | Madrid |
| Advanved Soluciones | Valencia |
| Advento Networks, S.L. | Madrid |
| Adventus Systems Iberica, S.L. | Madrid |
| ADW Europe, S.L. | Biscay |
| AEBAN | Madrid |
| Aeorum España, S.L. | |
| Aernnova Aerospace, S.A. | Álava |
| Aerocamaras, S.L. | Pontevedra |
| AEtech | Girona |
| Aeuroweb, S.L. | Valencia |
| AF Informática Aplicada, S.A.U. | Valencia |
| Affilired, S.L. | Balearic Islands |
| Affirma Biotech, S.L. | |
| Aforo10 | Balearic Islands |
| AFX Solutions, S.L.U. | Barcelona |
| Agarose Beads Technologies | |
| Agedum Sistemas de Información | Málaga |
| Agencia Amazon 360 | |
| Agencia de Ciencia, Competitividad Empresarial e Innovación Asturiana | Asturias |
| Agencia DGD | |
| Agencia Espacial Española | |
| Agencia Española de Medicamentos y Productos Sanitarios | |
| Agencia Española de Protección de Datos | Madrid |
| Agencia La Nave | |
| Agencia POP | Burgos |
| Agencia SEO | Valencia |
| Agencia SP | |
| Agenciate | |
| Aggity | Barcelona |
| AgileTV | |
| AgLa4D Construction Technology | |
| aGora | Castellón |
| Agritec Software | Barcelona |
| Agroges | Granada |
| Agroptima, S.L. | Barcelona |
| Ahead Therapeutics, S.L. | |
| AI Congress | Barcelona |
| AI ScreenWriter | Las Palmas |
| AI-Adventures | |
| AiAlaba | |
| Aiguasol | |
| AIJU Instituto Tecnológico de Producto Infantil y Ocio | |