| # | Company name | Role | # of projects |
|---|---|---|---|
| 1 | Rafael de La-Hoz Arquitectos | Architect | 32 |
| 2 | Realia Business | Developer | 6 |
| 3 | Reid-Fenwick Asociados | Architect | 5 |
| 4 | Renfe | Investor | 1 |
| 5 | Repsol-Ypf | Owner | 6 |
| 6 | Reyal Urbis, S.A. | Developer | 1 |
| 7 | Richard Rogers S.L. | Architect | 7 |
| 8 | RMD Kwikform | Formwork supplier | 0 |
| 9 | Rockwell Group Europe | Interior designer | 1 |
| 10 | Rodamco España S.A. | Real estate agent | 4 |
| 11 | RODIO Cimentaciones Especiales S.A. | Foundation company | 18 |
| 12 | Rodio Kronsa | Foundation company | 2 |
| 13 | Rogers Stirk Harbour + Partners S.L. | Architect | 3 |
| 14 | Rojo / Fernandez-Shaw | Architect | 1 |
| 15 | RTKL España | Architect | 0 |
| 16 | Rubio & Alvarez Sala | Architect | 3 |