| EnteroBiotix Ltd | |
| Enterprise League | |
| Enterprise Management 360 | |
| Enterprise Park Forres | |
| Enterprise Recruitment Ltd | Hertfordshire |
| Enterprise Research Centre | |
| Enterprise RPA | |
| Enterprise Software Systems | Greater Manchester |
| Enterprise Solutions (E-Sol) Ltd | |
| Enterprise Solutions (E-Sol) Ltd | North Yorkshire |
| Enterprise Therapeutics | |
| Enterware Ltd | |
| Entire Web Design | |
| Entnet Ltd | |
| Entos Pharmaceuticals | |
| entral Consultancy & Training Ltd | |
| Entrepreneur Handbook Ltd | |
| Entrepreneurial-Spark Ltd | |
| Entrian Solutions Ltd | Hertfordshire |
| Entropie Voice and Data | Buckinghamshire |
| Entropy | Buckinghamshire |
| Entroware | |
| entrustIT Ltd | Hampshire |
| Entrypoint Web Design & Marketing | Kent |
| Entyce Creative | |
| Env Studio Ltd | |
| Envelop Risk | |
| Envestors | |
| Envicta Software | |
| Envigo Ltd | Greater London |
| Environment Systems Ltd | |
| Envisage Digital | |
| Envisics | |
| Envision Online Ltd | Gloucestershire |
| enVisual | South Yorkshire |
| Envitia Group plc | |
| Envoke | |
| Enza Capital | |
| Enzai Technologies Ltd | |
| EOIN Technology | |
| Eonic Associates, LLP | Kent |
| eOrange Technology Ltd | |
| EOS Systems Ltd | Belfast |
| Eos Venture Partners Ltd | |
| eoSemi Ltd | Cheshire |
| eOsphere | |
| Epaccsys Ltd | Leicestershire |
| Epi Genesys Ltd | |
| Epic IT Ltd | Hertfordshire |
| Epic New Media | |