| Extract Studio Ltd | |
| Extract Technology Ltd | |
| ExtraDigital Ltd | |
| ExtraMile Communications | Staffordshire |
| Extraordinary Managed Services Ltd | Edinburgh |
| ExtraScope Ltd | Rhondda Cynon Taf |
| Extravision | Greater Manchester |
| Extreme Creations Ltd | North Yorkshire |
| Exus | Greater London |
| Exvastat Ltd | |
| EyA | Greater London |
| Eye for Marketing | |
| Eye Revolution London | Greater London |
| EyeBio | |
| eyeCon Vista | North Yorkshire |
| Eyespace Digital | |
| Eyesparks | Belfast |
| Eyeweb Solutions Ltd | East Riding of Yorkshire |
| ez Web Solutions | Hertfordshire |
| eZe-Talk Ltd | Cheshire |
| Ezi Solution | Surrey |
| Ezitracker Ltd | Staffordshire |
| ezofficesystems Ltd | Hampshire |
| EZPZ Software Ltd | South Yorkshire |
| Ezulix | |
| F One Technologies | |
| F# Software Foundation | Cambridgeshire |
| F&L Accessories Ltd | Gloucestershire |
| F-Prime Capital | |
| F-star Therapeutics Ltd | |
| F10 Software Solutions | |
| F1000 Research Ltd | |
| F1Group | Lincolnshire |
| F2B Sites | |
| F2G Ltd | |
| F6S Network Ltd | |
| Fablr Ltd | |
| FabricNano | |
| Fabrinet UK Ltd | Wiltshire |
| Fabrique.ai Ltd | |
| FaceApp Technology Ltd | |
| Facia.ai | |
| Facit Data Systems | |
| Factory24 | |
| Factory37 | Glasgow |
| Faculty | |
| Faelix Consultancy Services | Greater Manchester |
| Fagan Jones Communications Ltd | |
| Fagus Antibody Services Ltd | |
| FairHQ Ltd | |