| Fire Engine Red Limited | Professional & scientific | 2015 |
| Fire Protection Advisory Services Ltd | Public administration | 2017 |
| Fireprotectservicesuk Limited | Public administration | 2020 |
| Firmitas Design and Build Ltd | Construction | 2020 |
| First Chauffeurs Ltd | Transport & logistics | 2025 |
| First Choice Car Sales Kent Ltd | Wholesale & retail | 2026 |
| First Class Brentwood Ltd | Other services | 2017 |
| First Heating & Property Services Limited | Construction | 2018 |
| First Sports Management Ltd | Administrative & support | 2015 |
| Fisdhsis Ltd | Construction | 2026 |
| Fise Holdings Limited | Hospitality | 2016 |
| Fishing Maniacs Limited | Arts & recreation | 2020 |
| Fisk Property Limited | Real estate | 2025 |
| Fitsolution Training Ltd | Arts & recreation | 2018 |
| Fitted Furniture Creations Limited | Construction | 2020 |
| Fitzherbert Developments Ltd | Construction | 2022 |
| Five Fitness TH Limited | Wholesale & retail | 2022 |
| Five Group Limited | Wholesale & retail | 2022 |
| Five Investments Limited | Real estate | 2022 |
| Fixed FEE Wealth Management Limited | Extraterritorial | 2013 |
| FJF Memorial Homes Limited | Health & social care | 2023 |
| FJK Safety Limited | Administrative & support | 2016 |
| FL7 Limited | Administrative & support | 2023 |
| Flamerite Fires Limited | Manufacturing | 1999 |
| Flashbang Studio Limited | Information & communication | 2017 |
| Flats 1-7 Hawkley Mews RTM Company Ltd | Households | 2025 |
| Flav and Co Acquisition Ltd | Construction | 2023 |
| Flavour PR & Management Limited | Professional & scientific | 2016 |
| Flawless Faces Aesthetics Limited | Other services | 2019 |
| Flawless Faces Skin Ltd | Other services | 2017 |
| Fleetsmith Ltd | Wholesale & retail | 2023 |
| Fletcher Scenery Limited | Arts & recreation | 2018 |
| Fleur Wilde Limited | Wholesale & retail | 2026 |
| Flexi Holdings Ltd | Real estate | 2023 |
| Flexmirror-Uk Limited | Construction | 2024 |
| Flexwyse Ltd | Wholesale & retail | 2021 |
| Flick Fashions Limited | Wholesale & retail | 1980 |
| Flint Street Development Limited | Construction | 2025 |
| Flipping Genius Ltd | Real estate | 2024 |
| Flirt Lash & Brow Bar Ltd | Other services | 2025 |
| FLO Events Ltd | Hospitality | 2020 |
| FLO Promotions Ltd | Other services | 2013 |
| Flo-Mat Holding Ltd | Construction | 2020 |
| Float Nootropics Limited | Wholesale & retail | 2025 |
| Floating Focus Ltd | Professional & scientific | 2018 |
| Floorlines Direct Limited | Wholesale & retail | 2008 |
| Floorsave London Limited | Wholesale & retail | 2013 |
| Flopz Limited | Wholesale & retail | 2013 |
| Florabella Ltd | Wholesale & retail | 2022 |
| Florin Maxim Limited | Transport & logistics | 2017 |
| Flow Media Solutions Ltd | Information & communication | 2005 |
| Flower Perfections Ltd | Wholesale & retail | 2009 |
| Flynn & White Properties Ltd | Real estate | 2025 |
| FM & Estates Services Ltd | Administrative & support | 2026 |
| Fmcg Springboard Ltd | Professional & scientific | 2014 |
| Fmly Agency Ltd | Arts & recreation | 2015 |
| Focus Drylining Limited | Construction | 2009 |
| Focus on Banking Limited | Professional & scientific | 2000 |
| Fogg Electrical Services Limited | Construction | 2013 |
| Foley Building Contracts Ltd | Administrative & support | 2010 |
| Foman Limited | Construction | 2018 |
| Foodie Roots Solutions Ltd | Administrative & support | 2023 |
| Foodilize Limited | Information & communication | 2020 |
| Football 1 X 2 Limited | Information & communication | 2003 |
| Footy MAD Limited | Extraterritorial | 2009 |
| Foravia Limited | Professional & scientific | 2025 |
| Forbidden Planet (Belfast) Ltd | Wholesale & retail | 1998 |
| Forbidden Planet International Limited | Wholesale & retail | 2000 |
| Forde Cinta Services Limited | Agriculture & fishing | 2025 |
| Fordham Creative Ltd | Professional & scientific | 2024 |
| Foremost Partners UK Ltd | Professional & scientific | 2017 |
| Forest Accountancy Services Limited | Professional & scientific | 2016 |
| Forest Box Co. Limited | Manufacturing | 1988 |
| Forest Drives Limited | Construction | 2003 |
| Forever Younger Limited | Administrative & support | 2022 |
| Forjo Ltd | Professional & scientific | 2018 |
| Formula Auto Paints Limited | Wholesale & retail | 2024 |
| Formula Car Paints Limited | Wholesale & retail | 2024 |
| Formula Fitness Limited | Arts & recreation | 2025 |
| Forrest Engineering Ltd | Professional & scientific | 2018 |
| Fortes 3 Design Ltd | Professional & scientific | 2015 |
| Fortis International Limited | Transport & logistics | 2019 |
| Fortuna Karma Ltd | Wholesale & retail | 2022 |
| Fortuna Thai Limited | Hospitality | 2022 |
| Fortunatum Limited | Professional & scientific | 2022 |
| Fortune and Coates Ltd | Real estate | 2020 |
| Forum Concepts Limited | Professional & scientific | 2009 |
| Foster Ashbury Construction Ltd | Administrative & support | 2016 |
| Foster Ashbury Property Development Ltd | Real estate | 2016 |
| Four Corners Padel Limited | Arts & recreation | 2026 |
| Four Flames Foods Limited | Hospitality | 2026 |
| Four Motion Physiotherapy Ltd | Professional & scientific | 2021 |
| Four Seasons AC Ltd | Energy | 2024 |
| Four Smiths Limited | Real estate | 2016 |
| Foureighty Coffee Limited | Wholesale & retail | 2020 |
| Foureighty Limited | Other services | 2015 |
| Fourscore Mansions Freehold Company Limited | Households | 2016 |
| Fowler Wealth Limited | Financial services | 2021 |
| FOX Design International Limited | Professional & scientific | 1990 |
| FOX International Group Limited | Manufacturing | 1973 |