| RTM Solution Mantenimiento Informático | Madrid |
| Rubén M. Tous González | |
| Rubiras | |
| Rural Servicios Informáticos, S.L. | Madrid |
| Rviewer | Barcelona |
| S&C Automatismos de Seguridad | Cádiz |
| S&M Services | Biscay |
| S.M.E. Instituto Nacional de Ciberseguridad de España M.P., S.A. | León |
| S2 Grupo | |
| S21Sec | Gipuzkoa |
| Sabadell Digital, S.A.U. | Barcelona |
| Sabadell Venture Capital | Barcelona |
| SADMedia | Madrid |
| Safeline, S.L. | Barcelona |
| Safeloc Systems, S.L. | Gipuzkoa |
| Sagsystem | |
| SAI Computers | Barcelona |
| Sale Systems | Madrid |
| Sales Layer | Valencia |
| Salvat | Barcelona |
| Samara | Madrid |
| SAMELAN. Soluciones Tecnológicas, S.L. | Madrid |
| Samsung Electronics Iberia, S.A. | Madrid |
| Samy Road, S.L. | |
| Sanabre Comunica | Barcelona |
| Sangar Computer, S.L. | Badajoz |
| Sanifit | Balearic Islands |
| Santa Clara Tech | Madrid |
| Santa Mónica Soluciones Informáticas | León |
| Santana Jerez, S.L. | Las Palmas |
| Santander Teleport | |
| Santander X | Madrid |
| SAPAS Consulting, S.L. | Barcelona |
| Sapiens Talent | Madrid |
| SAPIMSA | Madrid |
| Saqqara Informática | Madrid |
| Sare-Berri | Gipuzkoa |
| Sarenet | Biscay |
| SareSoft Aplicaciones on Line, S.L. | Biscay |
| SareTech | Navarre |
| Sarpanet | Cantabria |
| SAT CIT | Madrid |
| Satdata | A Coruña |
| SATEC | Madrid |
| Sateliot | Barcelona |
| Satinfo, S.L. | Barcelona |
| Satlantis | |
| Satlink, S.L. | |
| Satydal Comunicaciones | Málaga |
| Sauco Consulting | Zaragoza |