| Fissara Solutions Limited | Wholesale & retail | 2023 |
| Fit to Dance (UK) Limited | Wholesale & retail | 2007 |
| Fitcamp Women Ltd | Other services | 2018 |
| Fitness Products Experts Ltd | Other services | 2020 |
| Fitting Rooms Limited | Construction | 2019 |
| Fitzgerald Analytics Limited | Professional & scientific | 2024 |
| Fitzgerald Limited | Professional & scientific | 2026 |
| Fitzroy Coffee Ltd | Hospitality | 2025 |
| Five North Digital Ltd. | Real estate | 2014 |
| Five Rainbows Group Limited | Financial services | 2026 |
| Five Stars Engineering Limited | Administrative & support | 2007 |
| Fixx Salons Ltd | Other services | 2018 |
| Fjoralba and Sons Limited | Health & social care | 2021 |
| FJT Services Limited | Professional & scientific | 2023 |
| FK Maintain Limited | Construction | 2015 |
| FKI Medics Ltd | Health & social care | 2026 |
| Flair Boutique UK Ltd | Wholesale & retail | 2019 |
| Flash Property Ltd | Real estate | 2018 |
| Flashnik Limited | Manufacturing | 2014 |
| Flatware Limited | Wholesale & retail | 2007 |
| Flauron Digital Ltd | Information & communication | 2025 |
| Fledgling Capital Ltd | Financial services | 2025 |
| Fleet Tracking Consultancy Limited | Information & communication | 2021 |
| Fletcher & Yearsley Properties Limited | Real estate | 1999 |
| Fletcher Legal Services Limited | Administrative & support | 2010 |
| Flett Rentals Ltd | Real estate | 2024 |
| Flexographic Industry Association UK Ltd | Other services | 1978 |
| Flexpoint Ltd | Administrative & support | 1997 |
| Flight Bidco Limited | Financial services | 2025 |
| Flight Midco Limited | Financial services | 2025 |
| Flight Technology Ltd | Information & communication | 2014 |
| Flightdelayrepay Limited | Information & communication | 2017 |
| Floor Space Limited | Real estate | 2001 |
| Floreeda Fabrications Limited | Manufacturing | 1990 |
| Florence Corp. Limited | Financial services | 2016 |
| Florence Petroleum Ltd | Mining & quarrying | 2020 |
| Flores Investments Limited | Financial services | 2022 |
| Flow UK Holdco Limited | Financial services | 2025 |
| Flowcode UK Limited | Information & communication | 2023 |
| Flowfocus Limited | Hospitality | 2000 |
| Flowspark Limited | Administrative & support | 2024 |
| Flowtrain Limited | Professional & scientific | 1989 |
| Flsmidth (UK) Limited | Administrative & support | 1925 |
| Fluent Human Limited | Professional & scientific | 2023 |
| Fluid Sourcing and Development Limited | Wholesale & retail | 2009 |
| Fluid Wellness Limited | Other services | 2023 |
| Fluidstack Argentina Holdings I Ltd | Information & communication | 2025 |
| Fluidstack Finland Holdings I Ltd | Information & communication | 2025 |
| Fluidstack France Holdings I Ltd | Information & communication | 2025 |
| Fluidstack Iceland Holdings I Ltd | Information & communication | 2025 |
| Fluidstack Infrastructure I Ltd | Information & communication | 2025 |
| Fluidstack Infrastructure Ltd | Information & communication | 2025 |
| Fluidstack Norway Holdings I Ltd | Information & communication | 2025 |
| Fluidstack USA Holdings I Ltd | Information & communication | 2025 |
| Flumlite Technologies Ltd | Manufacturing | 2022 |
| Fluush Limited | Information & communication | 2019 |
| Fluxbyte Limited | Information & communication | 2021 |
| FLW Consultancy Limited | Professional & scientific | 2026 |
| Flxev UK Ltd. | Financial services | 2025 |
| FMG (Holdings) Limited | Professional & scientific | 2016 |
| FMS Interior Services Holdings Ltd | Financial services | 2026 |
| FMS Interior Services Ltd | Wholesale & retail | 2007 |
| Focal Vale Limited | Administrative & support | 2005 |
| Focus Creative Consultancy Ltd | Other services | 2023 |
| Focused Consulting Limited | Administrative & support | 2004 |
| Focused Group Limited | Financial services | 2009 |
| Focused Payment Services Limited | Administrative & support | 2013 |
| Focusforward Ltd | Education | 2025 |
| Folie Leisure Limited | Hospitality | 2023 |
| Fondapp Holdings Ltd | Financial services | 2017 |
| Food by Sarah Limited | Hospitality | 2021 |
| Food Dream International Limited | Financial services | 2020 |
| Food Jury Ltd | Hospitality | 2024 |
| Food Styles Sourcing Solutions Ltd | Professional & scientific | 2020 |
| Football Room Ltd. | Information & communication | 2024 |
| Footprint Property Services Limited | Real estate | 2005 |
| FOR Real Training and Events Management C.I.C. | Arts & recreation | 2014 |
| Forbes Builders Ltd | Construction | 2019 |
| Forbes Dawson Ltd | Professional & scientific | 2013 |
| Forculture Limited | Professional & scientific | 2022 |
| Forecast Technologies Group Limited | Information & communication | 2021 |
| Forecast Technologies Limited | Information & communication | 2019 |
| Forecast Technologies Trading Limited | Information & communication | 2023 |
| Foredra Limited | Other services | 2025 |
| Foresight Independent Financial Planning Limited | Financial services | 2006 |
| Foresight Wealth Group Limited | Financial services | 2021 |
| Forest Holidays Group Limited | Administrative & support | 2012 |
| Forest Intermediate Holdings UK Limited | Financial services | 2023 |
| Forever Legal Limited | Professional & scientific | 2019 |
| Foreversure Limited | Financial services | 2025 |
| Forge Finance Solutions Limited | Professional & scientific | 2024 |
| Forge Flip Homes Ltd | Real estate | 2025 |
| Forgefront Ltd | Professional & scientific | 2022 |
| Form Consultancy Limited | Administrative & support | 2013 |
| Formatt Holdings Limited | Financial services | 2020 |
| Formatt Limited | Wholesale & retail | 1998 |
| Forme Construction Limited | Construction | 2025 |
| Formula C Limited | Administrative & support | 2026 |
| Forrest Hill Management Company Limited | Households | 1997 |
| Forreston Developments Limited | Real estate | 2026 |