| # | Company name | Role | # of projects |
|---|---|---|---|
| 1 | Ecosistema Urbano Arquitectos | Architect | 0 |
| 2 | ECOVI S.A. | Developer | 0 |
| 3 | EIPSA | Civil engineering | 1 |
| 4 | El Corte Inglés | Owner | 13 |
| 5 | Elecnor | MEP engineering | 7 |
| 6 | Elecnor, S.A. | Electrical connections | 0 |
| 7 | Empresa Municipal de la Vivienda y Suelo de Madrid, S.A. | Developer | 1 |
| 8 | Empresas Emiliano Madrid | Facade supplier | 1 |
| 9 | Endesa S.A. | Owner | 1 |
| 10 | Enrique Álvarez | Architect | 1 |
| 11 | Envest Consultancy | Environmental consultant | 0 |
| 12 | Ercilla & Campo | Architect | 1 |
| 13 | Ericsson España S.A. | Client | 0 |
| 14 | Espacio S.A. | Floor installation | 5 |
| 15 | Estudio Arquitectura Campo Baeza | Architect | 4 |
| 16 | Estudio Entresitio | Architect | 1 |
| 17 | Estudio Lamela Arquitectos | Architect | 14 |
| 18 | Estudio Martin Caballero Arquitectos | Architect | 1 |
| 19 | ETRA Arquitectos S.L. | Architect | 1 |
| 20 | Exa Consulting Investment | Consultancy | 0 |