| Name | Region |
|---|---|
| MLT Digital | |
| MMC Research & Marketing Ltd | |
| MMC Ventures Ltd | Greater London |
| MMD | Berkshire |
| MMS Electronics Ltd | West Yorkshire |
| MMT Digital | Rutland |
| MMTIW | South Ayrshire |
| MMTM Ltd | |
| MNA Digital | |
| MNB Networks Ltd | |
| Mo | Greater London |
| Mo-Sys Engineering Ltd | |
| Moa Technology Ltd | |
| Mobell Communications Ltd | Staffordshire |
| Mobilarm | Hampshire |
| Mobile Acuity Ltd | Edinburgh |
| Mobile App Developers UK | |
| Mobile App Experts | |
| Mobile Europe | |
| Mobile GIS Services | |
| Mobile Guardian | |
| Mobile Input Types | |
| Mobile PC Guru | |
| Mobile Phones | Hampshire |
| Mobile Phones Direct | Berkshire |
| Mobile Pie Ltd | Bristol |
| Mobile Power Ltd | |
| Mobile Techie | Berkshire |
| Mobile Tornado plc | |
| mobileArt | |
| MobileCashMate | West Midlands |
| MobileMinder | |
| Mobilepartz | Cornwall |
| MobilePhoneApps Ltd | |
| MobileTornado | North Yorkshire |
| Mobilise Care Ltd | |
| MobiLoud | |
| Mobilus Labs Ltd | |
| Mobius Networks Ltd | Leicestershire |
| Mobysoft | |
| Mocean Energy | |
| Modal | |
| Modern Democracy | |
| Modern English Digital | |
| Modex | Greater London |
| Modgraph | Hertfordshire |
| Modo Energy | |
| Modo25 | West Yorkshire |
| Modular Digital | |
| Module Studio |