| Fixed Locally | |
| Fixtuur | |
| FIZZ designs & SEO | |
| Fizz Software Ltd | Essex |
| fizzPOP | |
| FJB Digital Ltd | East Lothian |
| FJC Systems | Lancashire |
| FK Accelerate | |
| FL1 Digital | |
| Flagsmith | |
| Flagstone Group Ltd | |
| Flagstone Software Ltd | Highland |
| Flame Design | |
| Flame SEO | Cheshire |
| Flamingoat Ltd | Leicestershire |
| Flann Microwave Ltd | Cornwall |
| Flare Software Ltd | Bristol |
| Flare Web Ltd | Dorset |
| Flash UK | Scottish Borders |
| Flashbay Ltd | Greater London |
| Flask Ltd | |
| Flat Rock Technology Ltd | |
| FlatFair | Greater London |
| Flavourworks | |
| Flaydemouse Media Ltd | Somerset |
| Fleek Marketing | |
| Fleet Optimise | West Midlands |
| Fleetly | |
| Fleetview Solutions Ltd | |
| Fleksy | |
| Fletcher Ward Design Ltd | |
| Flex Systems | Cardiff |
| Flex4 | |
| Flexa | Greater London |
| Flexciton Ltd | |
| FlexEnable Technology Ltd | |
| Flexi Time Planner Ltd | West Yorkshire |
| Flexible & Specialist Cables | Hertfordshire |
| Flexible Lab Solutions | |
| Flexible Software Ltd | Oxfordshire |
| Fleximize Ltd | |
| Flexioffices Ltd | |
| Flexiscale | West Lothian |
| Flexiweb Digital | |
| Flexkeeping | |
| Flexkeeping Ltd | Greater London |
| FLG Business Technology Ltd | Lancashire |
| FlickThru | East Sussex |
| Flint Consulting | Hertfordshire |
| Flint Studios Ltd | Belfast |