| Flawless Financial Consultants Ltd | Professional & scientific | 2011 |
| Fleetright Limited | Manufacturing | 2021 |
| Fletcher Court Management Limited | Households | 1985 |
| Flex Assist London Ltd | Professional & scientific | 2026 |
| Flex Exhibition Ltd | Administrative & support | 2024 |
| Flexible Work Solutions Ltd. | Education | 2006 |
| Flexicap Limited | Other services | 2023 |
| Flexshiftremovals Ltd | Transport & logistics | 2025 |
| FLG Consulting Services Ltd | Professional & scientific | 2026 |
| Flights Hunt Ltd | Administrative & support | 2025 |
| Flintfix Limited | Manufacturing | 2025 |
| Floating Armour Ltd | Information & communication | 2026 |
| Floor Heat Innovation Ltd | Construction | 2024 |
| Floor Talk Limited | Construction | 2021 |
| Flooring Scene Ltd | Construction | 2024 |
| Floortech Contracts Limited | Construction | 2018 |
| Flora Select Limited | Agriculture & fishing | 2004 |
| Florence Court (Knebworth) Management Company Limited | Real estate | 2020 |
| Flotto Limited | Professional & scientific | 2025 |
| Floveda Homes Limited | Real estate | 2026 |
| Flow Dynamics Engineering Ltd | Professional & scientific | 2026 |
| Flower Skincare Limited | Manufacturing | 2025 |
| Flowlet Ltd | Real estate | 2026 |
| Flumaion Ltd | Information & communication | 2018 |
| Flume International Limited | Manufacturing | 2023 |
| Flumpet Enterprises Limited | Real estate | 2022 |
| FLY SKI Racing Ltd | Arts & recreation | 2023 |
| Flyworld Overseas Services Ltd | Administrative & support | 2021 |
| FMG Ltd | Administrative & support | 2024 |
| Fnly Property Group Ltd | Real estate | 2024 |
| Focused Facilities Management Ltd | Extraterritorial | 2016 |
| FOCUSMED24 Ltd | Administrative & support | 2008 |
| Fodo Business Services Limited | Health & social care | 2012 |
| Foley Investments Limited | Construction | 2009 |
| Follyfield Properties Limited | Real estate | 2024 |
| Fonix Telematics Limited | Transport & logistics | 2009 |
| Font Creative Ltd | Arts & recreation | 2017 |
| Font Holdings Ltd | Wholesale & retail | 2026 |
| Food Brokers UK Limited | Wholesale & retail | 2023 |
| Food Physics Group Limited | Professional & scientific | 2019 |
| Food Physics Ltd | Professional & scientific | 2013 |
| Fooderia Ltd | Hospitality | 2025 |
| Foot Golf Wise Limited | Arts & recreation | 2015 |
| Football FUN Factory (Community 130) Limited | Arts & recreation | 2024 |
| FOR Every Gamer C.I.C. | Manufacturing | 2025 |
| FOR for Prod Limited | Information & communication | 2023 |
| Forbes Farriery Limited | Professional & scientific | 2010 |
| Force Cloud Ltd | Information & communication | 2022 |
| Force Cricket Ltd | Arts & recreation | 2026 |
| Force TEN Holdings Ltd | Real estate | 2026 |
| Forcentriq Limited | Information & communication | 2023 |
| Forefield Residents Association Limited | Households | 1977 |
| Foreman MJ Limited | Extraterritorial | 2019 |
| Forest Contracts Limited | Manufacturing | 1997 |
| Forest Homecare Limited | Health & social care | 1997 |
| Forest Wealth Management Ltd | Financial services | 2025 |
| Foretell Digital Limited | Information & communication | 2016 |
| Forever Jewel Ltd | Wholesale & retail | 2025 |
| Forge Billericay CM12 Ltd | Hospitality | 2025 |
| FORGE9X Ltd | Wholesale & retail | 2025 |
| Forget ME NOT Caring Ltd | Health & social care | 2011 |
| Forklift Parts Centre Limited | Wholesale & retail | 2007 |
| Form & Thread Limited | Wholesale & retail | 2013 |
| Form Wear Ltd | Wholesale & retail | 2026 |
| Formally Suited Limited | Wholesale & retail | 2024 |
| Forme Pilates Ltd | Arts & recreation | 2025 |
| Formulate Training Academy Limited | Education | 2022 |
| Forseti Search Ltd | Administrative & support | 2018 |
| Forte International Limited | Professional & scientific | 2020 |
| Forte Physical Health Ltd | Health & social care | 2016 |
| Forte Worldwide Limited | Construction | 2020 |
| Fortify Building Services Limited | Construction | 2016 |
| Fortify Facilities & Management Ltd | Construction | 2025 |
| Fortitude Global Logistics Holdings Ltd | Financial services | 2025 |
| Fortitude Global Logistics Ltd | Transport & logistics | 2016 |
| Fortresse Ltd | Information & communication | 2025 |
| Fortuna FX Holdings Limited | Financial services | 2023 |
| Fortuna FX Ltd | Financial services | 2020 |
| Fortuna Private Hire Limited | Administrative & support | 2023 |
| Fortune One Reality Limited | Real estate | 2019 |
| Fortune Safety & Transport Services Ltd | Transport & logistics | 2025 |
| Forum Services Limited | Information & communication | 2025 |
| Forward Your Network Limited | Information & communication | 2024 |
| Forza Finance Ltd. | Other services | 2016 |
| Fossicle Ltd | Professional & scientific | 2005 |
| Foster & NOY Ltd | Construction | 2015 |
| Fotoworx Limited | Professional & scientific | 1999 |
| Founders PG Limited | Extraterritorial | 1960 |
| Foundry Associates Limited | Professional & scientific | 2012 |
| Foundry Kowalski Ltd | Arts & recreation | 2024 |
| Four Chefs Ltd | Hospitality | 2020 |
| Four Oaks Publishing Limited | Information & communication | 2010 |
| Four Season Rooms Limited | Construction | 2024 |
| Four Seasons Discount Limited | Wholesale & retail | 2017 |
| Four Seasons Logistics Limited | Transport & logistics | 2020 |
| Four Seven's PVT Ltd | Real estate | 2024 |
| Four Stags Ltd | Real estate | 2020 |
| Four Winds (Essex) Limited | Financial services | 2020 |
| Fourboys Ventures Limited | Administrative & support | 2023 |
| Fourth Avenue Property Services Ltd | Real estate | 2018 |