| Forest Pennant Ltd | Mining & quarrying | 2015 |
| Forest School Learning Initiative Limited | Education | 2014 |
| Forester House Ltd | Administrative & support | 2018 |
| Forever Clinic Aesthetics Limited | Health & social care | 2019 |
| Forever Green Renewables Limited | Construction | 2012 |
| Forever Young Ventures Limited | Administrative & support | 2024 |
| Forge Resilience Coaching Ltd | Information & communication | 2026 |
| Forgeability Limited | Manufacturing | 2008 |
| Forgepoint Engineering Limited | Construction | 2025 |
| Forget ME NOT Forever Ltd | Extraterritorial | 2026 |
| Form Management Limited | Administrative & support | 2005 |
| Forma Mercatura Ltd | Wholesale & retail | 2025 |
| Formations NO 229 LLP | | 2016 |
| Formatsunny Limited | Professional & scientific | 2003 |
| Forrest Residential & Lettings Limited | Real estate | 2016 |
| Forrester Access Limited | Administrative & support | 2004 |
| Forrester Landscaping Limited | Administrative & support | 2005 |
| Forry Pet Care Limited | Professional & scientific | 2026 |
| Fortinbras Consulting Ltd | Professional & scientific | 2010 |
| Fortis Cardiff Limited | Extraterritorial | 2013 |
| Fortis Frontier PLC | Professional & scientific | 2008 |
| Fortix Capital Limited | Real estate | 2026 |
| Fortix Capital NO 2 Limited | Real estate | 2026 |
| Fortland Consulting Limited | Professional & scientific | 2014 |
| Fortuna FIC | Financial services | 2017 |
| Fortuna Property Investments Ltd | Real estate | 2021 |
| Fortuna Property Management Limited | Real estate | 2017 |
| Fortuna Property Portfolio Ltd | Financial services | 2021 |
| Fortuna Property R2R Ltd | Real estate | 2022 |
| Fortuna Property Services Ltd | Hospitality | 2021 |
| Fortune Engineering Ltd | Construction | 2025 |
| Fortune Equity Partners Limited | Financial services | 2025 |
| Forum Coffee Limited | Hospitality | 2025 |
| Forward Capital Investments Limited | Financial services | 2025 |
| Forward Group Holdings Limited | Financial services | 2024 |
| Forward Machines Limited | Wholesale & retail | 2024 |
| Forward Renewables Ltd | Energy | 2021 |
| Foscombe Properties Limited | Financial services | 2012 |
| Foscot T&D Services Limited | Professional & scientific | 2018 |
| Fosse Cross Properties Ltd | Transport & logistics | 2008 |
| Fosse Group 84 Limited | Administrative & support | 2023 |
| Fosse Kitchen Ltd | Hospitality | 2021 |
| Fosteringmatters Limited | Health & social care | 2004 |
| Fotescue Consultancy Limited | Information & communication | 2020 |
| Fotfp Limited | Real estate | 2016 |
| Foulkes Group Limited | Administrative & support | 2022 |
| Found One Ltd | Professional & scientific | 2024 |
| Founderbrook Limited | Real estate | 1971 |
| Founding Futures CIC | Education | 2024 |
| Foundry Zero Ltd | Information & communication | 2021 |
| Four Anjels Limited | Manufacturing | 2010 |
| Four by Two Build Limited | Real estate | 2016 |
| Four Corners Sports Management Ltd | Professional & scientific | 2015 |
| Four Lighting Limited | Wholesale & retail | 2025 |
| Four Oaks Developments Limited | Construction | 1977 |
| Four Quarters Polo 23 Limited | Extraterritorial | 2023 |
| Four Quarters Polo LLP | | 2009 |
| Four Seasons Publicity Limited | Public administration | 2013 |
| Four Squares Technology Ltd | Information & communication | 2025 |
| Four WET Paws Ltd | Professional & scientific | 2020 |
| Fourgate (Cheltenham) Limited | Real estate | 2017 |
| Fourthpath Limited | Other services | 2017 |
| Fowler Electrical Limited | Construction | 2011 |
| Fowler Sheldon Limited | | 1994 |
| Fowlers Consulting Services Limited | Information & communication | 2017 |
| FOX Creations Ltd | Professional & scientific | 2023 |
| FOX Food Services Ltd | Hospitality | 2014 |
| FOX Red Property Cotswolds Ltd | Real estate | 2025 |
| Foxcote Accounting Limited | Professional & scientific | 2014 |
| Foxcote Business Services Limited | Professional & scientific | 1999 |
| Foxcote House Riding School Limited | Arts & recreation | 2014 |
| Foxes Field Limited | Professional & scientific | 2001 |
| Foxetroo Ltd | Information & communication | 2014 |
| Foxhall Sporting Club Ltd | Arts & recreation | 2026 |
| Foxpack Holdings Ltd | Financial services | 2026 |
| Foxy INK Ltd | Other services | 2023 |
| Foxy Ladies Canape Co Limited | Hospitality | 2013 |
| Frah Consulting Limited | Professional & scientific | 2019 |
| Fran Trueman Limited | Extraterritorial | 2013 |
| Frances Court Management Company Limited | Real estate | 2009 |
| Frances Property Ltd | Real estate | 2022 |
| Francis & Co AFH Limited | Professional & scientific | 2018 |
| Francis Consulting Ltd | Professional & scientific | 2019 |
| Frank Holdings Limited | Financial services | 2025 |
| Frank Smith & Co Solicitors Limited | Professional & scientific | 2015 |
| Franki & Felix Ltd | Wholesale & retail | 2021 |
| Frankland (UK) Ltd | Construction | 2008 |
| Fraser Financial Planning Limited | Financial services | 2021 |
| Fraser Forestry Ltd | Agriculture & fishing | 2024 |
| Fraser's of Gloucester Limited | Wholesale & retail | 2000 |
| FRC Team Ltd | Administrative & support | 2024 |
| Free Acres Developments Ltd | | 2009 |
| Free to Perform Technology Group Ltd | Information & communication | 2018 |
| Freedom Consultancy International Ltd | Information & communication | 2026 |
| Freedom Hair Limited | Other services | 2020 |
| Freeland Properties Ltd | Real estate | 2019 |
| Freeland Residential LLP | | 2024 |
| Freeman Goddard & Associates Limited | Administrative & support | 2025 |
| Freestylextreme Trading Limited | Transport & logistics | 2009 |
| Frejus Limited | Financial services | 2017 |