| Fitzgerald Flooring Ltd | Construction | 2014 |
| Fitzroy Crossing Limited | Construction | 2013 |
| FIV Construction Ltd | Construction | 2017 |
| Five Healthcare Limited | Wholesale & retail | 2018 |
| Five Litigation Assist Limited | Financial services | 2009 |
| Five Pillars Engineering Ltd | Professional & scientific | 2025 |
| Five Points Developers Ltd | Financial services | 2023 |
| Five Points Properties Ltd | Financial services | 2023 |
| Five Points Ventures Ltd | Construction | 2023 |
| Five Rivers Logistics Limited | Transport & logistics | 2010 |
| Five Rivers Motors Ltd | Wholesale & retail | 2017 |
| Five Rivers Wealth Limited | Construction | 2019 |
| Five Star Greece Limited | Administrative & support | 2004 |
| Five Stars Harrow Limited | Wholesale & retail | 2024 |
| Five Talent Management Ltd | Professional & scientific | 2019 |
| Five to Watch Limited | Information & communication | 2010 |
| Five Twentyfive Limited | Information & communication | 2004 |
| Fiveamun Limited | Professional & scientific | 2023 |
| FIX & Dial Limited | Wholesale & retail | 2025 |
| FIX IT Properties Ltd | Construction | 2025 |
| Fixed Group Ltd | Information & communication | 2018 |
| Fixed Investment Limited | Real estate | 2019 |
| Fixod Limited | Construction | 2026 |
| Fixupp Ltd | Construction | 2017 |
| Fizza Consulting Ltd | Information & communication | 2016 |
| FJ Building Ltd | Construction | 2014 |
| Fjib Limited | Education | 2023 |
| FJW Foil Prints Ltd | Information & communication | 2023 |
| FK Multimedia Ltd | Information & communication | 2023 |
| FK Rigging Services Limited | Information & communication | 2020 |
| Fkoncept Ltd | Administrative & support | 2017 |
| FL Construction London Ltd | Construction | 2019 |
| Flaere Ltd | Wholesale & retail | 2025 |
| Flag Bearer Limited | Information & communication | 2017 |
| Flags & More Ltd | Wholesale & retail | 2017 |
| Flagship Global Limited | Wholesale & retail | 2010 |
| Flagstones Investment Group 1 Ltd | Real estate | 2026 |
| Flagstones Investment Group Ltd | Real estate | 2024 |
| Flagstones Property Group Ltd | Real estate | 2022 |
| Flair Tech Ltd | Information & communication | 2017 |
| Flame Cars Chauffeur Limited | Transport & logistics | 2022 |
| Flame Cars Limited | Administrative & support | 2022 |
| Flame Tree Healthcare Ltd | Health & social care | 2013 |
| Flame Tree Travel Ltd | Administrative & support | 2023 |
| Flame-Tech Fire Protection Ltd | Construction | 2023 |
| Flamingo Gems Limited | Administrative & support | 2025 |
| Flamingo Iconique Limited | Administrative & support | 2022 |
| Flamingo Pharma (UK) Ltd | Wholesale & retail | 2014 |
| Flamino’S Holdings Limited | Professional & scientific | 2025 |
| Flamino’S Limited | Hospitality | 2025 |
| Flare Partners Ltd | Professional & scientific | 2024 |
| Flare Shisha Ltd | Wholesale & retail | 2013 |
| Flash Learning Limited | Education | 2022 |
| Flash Properties Ltd | Real estate | 2019 |
| Flash Services Direct Ltd | Other services | 2021 |
| Flashgale Limited | Hospitality | 1994 |
| Flashy Deals Ltd | Wholesale & retail | 2024 |
| Flat A-E 30 Roxeth Hill RTM Company Ltd | Households | 2023 |
| Flat C 16 Arlington Street Limited | Other services | 2017 |
| Flatfee Limited | Transport & logistics | 2002 |
| Flatpack Productions Ltd | Other services | 2002 |
| Flav Vape Ltd | Other services | 2022 |
| Flavaroma Ltd | Professional & scientific | 2011 |
| Flavio Ltd | Wholesale & retail | 2025 |
| Flavor Fussion Ltd | Hospitality | 2024 |
| Flavors & Aroma Ltd | Hospitality | 2025 |
| Flavour of SRI Lanka Ltd | Hospitality | 2025 |
| Flawless Beauty by Sheetal Ltd | Other services | 2017 |
| Fleek Travels Limited | Transport & logistics | 2023 |
| Fleet Travel Ltd | Professional & scientific | 2016 |
| Fleet Wine and Food Ltd | Wholesale & retail | 2025 |
| Fleetbond Limited | Information & communication | 2000 |
| Fleetgate Ltd | Real estate | 2020 |
| Fleethq Limited | Transport & logistics | 2025 |
| Fleetra Global Ltd | Transport & logistics | 2025 |
| Fleetwood Pier Properties Limited | Real estate | 1967 |
| Fleetwood Prestige Limited | Wholesale & retail | 2013 |
| Flex Construct Limited | Construction | 2016 |
| Flexbell Solutions Limited | Real estate | 2009 |
| Flexectrix Ltd | Construction | 2018 |
| Flexgrove Properties Limited | Real estate | 2012 |
| Flexi 360 Health Care Limited | Health & social care | 2024 |
| Flexi Financial Accountant Ltd | Professional & scientific | 2013 |
| Flexi Financial Solutions Limited | Professional & scientific | 2008 |
| Flexi Online Ltd | Wholesale & retail | 2023 |
| Flexi Property Development Ltd | Real estate | 2017 |
| Flexible Solutions Limited | Health & social care | 2022 |
| Flexpower Limited | Real estate | 2011 |
| Flexward Limited | Real estate | 2011 |
| Flexx Service Centre Limited | Wholesale & retail | 2014 |
| Flick Brow and Lash Bar Ltd | Other services | 2022 |
| Flight Beyond Sight Limited | Transport & logistics | 2019 |
| Flights Experts Ltd | Administrative & support | 2010 |
| Flilid Ltd | Transport & logistics | 2023 |
| Flint Edge Limited | Wholesale & retail | 2003 |
| Flippers Swim School Northwood Limited | Education | 2024 |
| FLN Development Solutions Limited | Professional & scientific | 2023 |
| FLO Art Deco Ltd | Construction | 2019 |
| FLO Keef Ltd | Manufacturing | 2002 |
| Flomat Limited | Construction | 2017 |