| FAN Care Solutions Ltd | Health & social care | 2020 |
| FAN DC1 Limited | Transport & logistics | 2021 |
| FAN Film Limited | Information & communication | 2016 |
| Fancy Express Ltd | Wholesale & retail | 2023 |
| Fancy Media Communication Limited | Information & communication | 2012 |
| Fantastic Fireworks Limited | Arts & recreation | 1985 |
| Fantastic Mechanical Services Ltd | Construction | 2023 |
| Faraday Technical Services Limited | Transport & logistics | 2016 |
| Fareha Abid Limited | Wholesale & retail | 2025 |
| Farhin Chowdhury Ltd | Public administration | 2026 |
| Fariad & Sons Ltd | Hospitality | 2025 |
| Faridheit Limited | Information & communication | 2023 |
| Farkas Pall Medical Ltd | Health & social care | 2016 |
| Farley Building Services Limited | Construction | 2018 |
| Farley Chem Limited | Wholesale & retail | 2014 |
| Farley Community Group C.I.C. | Public administration | 2024 |
| Farley Hill Fish Bar Ltd | Hospitality | 2024 |
| Farley Hill Jame Masjid Limited | Other services | 2025 |
| Farley Hill Jame Masjid Luton Limited | Other services | 2025 |
| Farley Ltd | Real estate | 2023 |
| Farndale Systems Limited | Professional & scientific | 2025 |
| Farney Services Limited | Construction | 2018 |
| Faro's Restaurant Limited | Hospitality | 2026 |
| Farrer Lodge Management Company Limited | Real estate | 2014 |
| Fartak Puyan London Limited | Professional & scientific | 2024 |
| Farzanas Beauty Limited | Other services | 2019 |
| FAS (Luton) Holdings Limited | Financial services | 2019 |
| FAS Advisory Limited | Professional & scientific | 2023 |
| Fascel Group Holdings 2021 Limited | Construction | 2021 |
| Fascel Group Holdings Limited | Professional & scientific | 2016 |
| Fascel Group Limited | Construction | 1989 |
| Fascel Holdings Limited | Administrative & support | 2008 |
| Fascel MEP Limited | Construction | 2021 |
| Fascia & Glazing Supplies Limited | Wholesale & retail | 2006 |
| Fashion Expo Ltd | Wholesale & retail | 2021 |
| Fashion Marks 77 Limited | Wholesale & retail | 2025 |
| Fashion Runners Limited | Wholesale & retail | 2007 |
| Fashion Vibez Ltd | Wholesale & retail | 2025 |
| Fashion Zone Direct Limited | Manufacturing | 2015 |
| Fashionvilla Limited | Wholesale & retail | 2018 |
| Fashmosh Railnet Ltd. | Administrative & support | 2014 |
| Fask Care Consultancy Ltd | Health & social care | 2023 |
| Fast Courier Aoda Ltd | Other services | 2016 |
| Fast FIX MOT Center Limited | Wholesale & retail | 2025 |
| Fast Food Supplies Ltd | Hospitality | 2019 |
| Fast Heat Plumbing and Heating Limited | Construction | 2013 |
| Fast KRT Ltd | Construction | 2019 |
| Fast Marius Ltd | Transport & logistics | 2018 |
| Fast Private Plates Ltd | Other services | 2018 |
| Fast Rent Luton Ltd | Financial services | 2010 |
| Fast Resource & Management Enterprises Ltd | Administrative & support | 2025 |
| Fast Screeding Ltd | Construction | 2020 |
| Fast Track Auto's Limited | Wholesale & retail | 2012 |
| Fast Track Driving Limited | Education | 2024 |
| Fast Track Rental Ltd | Administrative & support | 2016 |
| Fast Track Vehicle Rentals Limited | Administrative & support | 2025 |
| Fast Wheel Autos Ltd | Information & communication | 2025 |
| Fast&Smart Removals Ltd | Transport & logistics | 2024 |
| Fasttrack AK Ltd | Transport & logistics | 2023 |
| Fasttracksupport Ltd | Information & communication | 2025 |
| Fastway AI Solutions UK Limited | Information & communication | 2025 |
| FAT With Time Ltd | Wholesale & retail | 2021 |
| Fatema Food Ltd | Hospitality | 2025 |
| Fatherhood Community Solutions CIC | Health & social care | 2013 |
| Fatima Asian Designer Clothes Ltd | Wholesale & retail | 2013 |
| Fatima Collection Ltd | Wholesale & retail | 2024 |
| Fatima Digit Ltd | Wholesale & retail | 2025 |
| Fatimah Ali-Mehdi Investments Ltd | Real estate | 2024 |
| Fatimah Transport Services Ltd | Transport & logistics | 2026 |
| Fattah Property Ltd | Real estate | 2025 |
| Favor ME Healthcare Services Ltd | Health & social care | 2024 |
| Faynno Limited | Wholesale & retail | 2026 |
| Fayra Accountants Ltd | Professional & scientific | 2013 |
| FAZ AL Kousar Company Ltd | Other services | 2025 |
| FAZ Trading Private Limited | Wholesale & retail | 2025 |
| Fazaan Locum Ltd | Wholesale & retail | 2020 |
| Fazil Optical Ltd. | Health & social care | 2025 |
| FB Cars Ltd | Wholesale & retail | 2023 |
| FBC & Associates Limited | Health & social care | 2021 |
| FC Park Homes Ltd | Real estate | 2022 |
| FC Peri Peri Ltd | Manufacturing | 2023 |
| FC SRI Ltd | Real estate | 2023 |
| FCC Asset Holdings Ltd | Transport & logistics | 2016 |
| Fcrb 1923 Limited | Transport & logistics | 2018 |
| Fcscap Limited | Professional & scientific | 2018 |
| FD One Systems Ltd | Manufacturing | 2011 |
| FDC Design Ltd | Construction | 2017 |
| FDS Property Holdings Ltd | Real estate | 2016 |
| Fdsproperties Ltd | Financial services | 2023 |
| FE Development Ltd | Administrative & support | 2013 |
| FE Direct Ltd | Education | 2025 |
| Feasthub Limited | Hospitality | 2026 |
| Featherstone Batteries Limited | Extraterritorial | 2022 |
| Febas Cleaning Services Limited | Administrative & support | 2026 |
| Febiri Holdings Limited | Real estate | 2024 |
| Fedon Ltd | Transport & logistics | 2019 |
| Feed ME More Ltd | Hospitality | 2024 |
| Feedver Ltd | Wholesale & retail | 2025 |
| Feel at Home Care Services CIC | Health & social care | 2025 |
| Feel Good Perfumes Limited | Wholesale & retail | 2026 |