| Founders Nation | |
| Foundries.io | |
| Foundry Visionmongers Ltd | |
| Foundry3 | |
| Fountain Digital Ltd | |
| Fountain Partnership | |
| Four Ages Software | |
| Four Business Solutions | |
| Four90 Designs | |
| FourFront Ltd | |
| Fourleaf Ltd | |
| Fourmeta | |
| FourNet | |
| FourPlus Immersive Ltd | |
| Fourth Generation Computer Group | Greater London |
| Fourth Monkey Ltd | Bedfordshire |
| FourthRev | |
| Fourway Communication | Hertfordshire |
| Fox Agency | |
| Fox Graphics Design | |
| Foxnose Ltd | |
| Foxnose Web Design Ltd | Glasgow |
| Foxxweb Design Ltd | Derbyshire |
| Fracas Digital Ltd | |
| Fractile | |
| Fractile Ltd | |
| Fractory Ltd | |
| Frame Communications Ltd | Suffolk |
| Frame Creative | Edinburgh |
| Framework Digital Ltd | |
| Framework Training Ltd | |
| Franchise Templates | |
| Francis Crick Institute Ltd | |
| Frank Whyte | |
| Fraser Murray | |
| Fraser Murray | |
| Fraser Web Design | South Lanarkshire |
| Freak Design Ltd | |
| Freda | Greater London |
| Free Range Web | |
| Free Rein Ltd | Suffolk |
| Free Virtual Servers | Leicestershire |
| FreeAgent | |
| Freecom Internet Services Ltd | West Midlands |
| Freedom Fibre | |
| Freedom of Speech Ltd | West Sussex |
| Freedom Search | |
| Freedom Software | South Yorkshire |
| Freedom Works | |
| FreedomNames | West Yorkshire |