| # | Company name | Role | # of projects |
|---|---|---|---|
| 1 | F&M Arquitectos | Architect | 0 |
| 2 | FCC Construcción | Construction company | 61 |
| 3 | Federico Aparici y Soriano | Architect | 1 |
| 4 | Federico Soriano | Architect | 8 |
| 5 | Félix Candela | Architect | 2 |
| 6 | Fernando Higueras Diaz | Architect | 1 |
| 7 | Ferran | Real estate agent | 0 |
| 8 | Ferrovial Agroman S.A. | Construction company | 52 |
| 9 | Ferrovial Inmobiliaria | Real estate agent | 10 |
| 10 | Fire-Stop Mediterraneo, S.A. | Fire protection engineering | 9 |
| 11 | Francisco de Cubas | Architect | 3 |
| 12 | Francisco Javier Sáenz de Oiza | Architect | 3 |
| 13 | FS Estructuras | Structural engineering | 2 |