| Idearte | Pontevedra |
| Ideas Para Nuevos Mercados, S.L. | Madrid |
| Idecnet, S.A. | Las Palmas |
| Ideesweb | Barcelona |
| Ideko | Gipuzkoa |
| Idemsoft, S.L. | Valencia |
| Idento | Granada |
| Idesoft Innovación, S.L. | Soria |
| IdeSoftware | Barcelona |
| Idesys Soluciones Informaticas, S.L. | Almería |
| Idodi Venture Capital, S.L. | Barcelona |
| Idoven | Madrid |
| IDP Pharma | Barcelona |
| IED Electronics Solutions, S.L. | Navarre |
| iEduca | Girona |
| iempresa | Madrid |
| IENAI SPACE | Madrid |
| IESA Comunidades Tecnológicas | Madrid |
| IESE Business School | Barcelona |
| Ifema Madrid | Madrid |
| IFFE Business School | |
| IFN Software, S.L. | Madrid |
| Igalia | A Coruña |
| Igasoft | A Coruña |
| Iglu Media | Girona |
| IgrafiQ | Barcelona |
| IGT Microelectronics, S.L. | Madrid |
| Iguana IT | Madrid |
| IKERLAN | |
| IKUSI | Gipuzkoa |
| Ilertec Consultoria Tecnologica, S.L. | Lleida |
| Ilimit Comunicacions, S.L. | Barcelona |
| iLine Microsystems, S.L. | Gipuzkoa |
| iLoveMG | Barcelona |
| iLovePDF | Barcelona |
| IloveSEO.net | Valencia |
| Ilunabar | Biscay |
| IM Projects | Barcelona |
| Imagina Web, S.L. | Barcelona |
| Imaginalia | Barcelona |
| Imaginart | Barcelona |
| Imagine Hub | Barcelona |
| Imatek.net | Barcelona |
| Imatia | Pontevedra |
| Imedia Comunicación | Albacete |
| IMF International Business School, S.L. | |
| IMH Campus | |
| IMK Digital Multimedia Corporation | Castellón |
| Immersive Pro | Madrid |
| IMMUNE Technology Institute | Madrid |