| # | Company name | Role | # of projects |
|---|---|---|---|
| 1 | 3C Capital Centro Comercial Development S.A. | Developer | 0 |
| 2 | A-Cero | Architect | 8 |
| 3 | A4 Arquitectos Asociados S.L. | Architect | 2 |
| 4 | Abalos & Herreros Arquitectos | Architect | 16 |
| 5 | Abalos+Sentkiewicz | Architect | 2 |
| 6 | Abarrategui | Architect | 2 |
| 7 | AEDAS Homes | Developer | 1 |
| 8 | Aeropuertos Españoles y Navegación Aérea | Client | 5 |
| 9 | Agofer | Real estate agent | 2 |
| 10 | Aguinaga y Asociados Arquitectos | Architect | 9 |
| 11 | Aguirre Newman | Property management | 16 |
| 12 | Alas Casariego Arquitectos | Architect | 1 |
| 13 | Alberto Martín de Lucio | Architect | 1 |
| 14 | Aldesa Construcciones | Construction company | 3 |
| 15 | Alkadir | Developer | 2 |
| 16 | Allende Arquitectos | Architect | 4 |
| 17 | Angel Hernández Espada | Architect | 1 |
| 18 | Antonio García Vereda | Architect | 1 |
| 19 | Antonio Lamela Martinez | Architect | 35 |
| 20 | Antonio Vázquez de Castro | Architect | 1 |