| Inxenio | A Coruña |
| ioBuilders | Madrid |
| IOMED | |
| IOMED | Barcelona |
| Ione Team | Madrid |
| IoT Stars | Barcelona |
| IPligence | Barcelona |
| IPM Electrónica, S.L. | Madrid |
| IPMark | Madrid |
| Ipo Networks | Alicante |
| iPractic | Barcelona |
| iPronics | Valencia |
| IPv6 Informatique, S.L. | Murcia |
| IQS Tech Factory | Barcelona |
| Iquadrat | Barcelona |
| IRB Barcelona | |
| IRC Computer | Málaga |
| Iris611 | Barcelona |
| IriusRisk | Huesca |
| Irontec | Biscay |
| IrsiCaixa | |
| isardSAT | Barcelona |
| ISDI Accelerator | Madrid |
| ISDI Digital Talent | Madrid |
| iSeazy | Madrid |
| iSencia, S.L. | Barcelona |
| Isigma Asesoría Tecnológica, S.L. | Barcelona |
| IslaWEB, S.L. | Balearic Islands |
| IspActiv | Barcelona |
| Istituto Europeo di Design S.p.A. | |
| IT Smart Finance Investment, S.L. | Barcelona |
| it&people, S.L. | Madrid |
| IT-Design | Málaga |
| Itaktion, S.L. | Gipuzkoa |
| ITCOM Telecomunicaciones, S.L.U. | Madrid |
| ITcSystem | Madrid |
| Iteisa | Cantabria |
| Item Multimedia, S.L. | Madrid |
| Itemvirtual, S.L.U. | Barcelona |
| Iteralix Enterprise, S.L. | Barcelona |
| ITGLOBAL | Barcelona |
| ITH Network, S.L. | Toledo |
| IThinkUPC | Barcelona |
| Itnig | Barcelona |
| iTools | Balearic Islands |
| ITSOFT | Sevilla |
| Ivanovich Games, S.L. | Barcelona |
| iVascular, S.L.U. | Barcelona |
| Ivigo Business School | Pontevedra |
| IVO Fundación Instituto Valenciano de Oncología | |