| Name | Region |
|---|---|
| Nuova Ceva S.n.c. | Novara |
| Nuovo Design | |
| NUR S.r.l. | |
| NurjanaTech | Cagliari |
| NUWA Technologies S.r.l. | |
| NWG S.p.A. | Prato |
| nXpire | |
| NyE Consulting | Parma |
| NYP Techfin | Rome |
| O&DS S.r.l. | |
| O-One S.r.l. | Milan |
| O.C.R. System | Turin |
| Objectway | Milan |
| OBLIQUID S.r.l. | Bergamo |
| OBS S.r.l. | Mantua |
| Octorate S.r.l. | |
| Octostar | |
| Oddi S.a.s. | Milan |
| Oem Automazione | Milan |
| Office Trade S.p.A. | Modena |
| OfficeJam | Rome |
| Officina Creativa | Brescia |
| Officina Stellare S.p.A. | |
| Officinae Bio S.r.l. | |
| Officine Informatiche S.r.l. | Frosinone |
| Officine Pixel | Forlì-Cesena |
| OHB Italia S.p.A. | |
| Ohm Space | |
| Ohm Space | |
| Ohoskin | |
| OKRIM S.n.c. | Vicenza |
| OLFA Technologies | Turin |
| Olivetti S.p.A. | Turin |
| Olon S.p.A. | |
| Oltre Consulenza | |
| Oltre Impact SGR S.p.A. | |
| Oltremare S.r.l. | Lodi |
| Omedra S.r.l. | Trento |
| Omicron Consulting S.r.l. | Turin |
| Omikron Italia S.r.l. | |
| Omitech | Padua |
| Omnia BPM | |
| Omnia Studio S.a.s. | Rome |
| Omnicon S.r.l. | Monza and Brianza |
| Omnidea S.r.l. | Venice |
| Omniink | Bari |
| Omnisoft S.r.l. | Milan |
| Omniworks | |
| Omnys S.r.l. | Vicenza |
| Onangel S.r.l.s. | Lecce |