| Flex Studio (Derby) Limited | Education | 2014 |
| Flexi Force Limited | Administrative & support | 2025 |
| Flexigroup Enterprises Limited | Education | 2024 |
| Fleximarble Investments Limited | Professional & scientific | 2025 |
| Flight Center UK Ltd | Administrative & support | 2026 |
| Flight Crew Transfers Ltd | Transport & logistics | 2025 |
| Flight Level Aviation Limited | Transport & logistics | 2017 |
| Flight Wise Limited | Administrative & support | 2024 |
| Flights Coach Travel Limited | Transport & logistics | 2020 |
| Flights Express Limited | Administrative & support | 2007 |
| Flint & Mortar Ltd | Real estate | 2026 |
| Flint Bishop Commercial Services Limited | Extraterritorial | 2022 |
| Flint Bishop Holdings Limited | Financial services | 2024 |
| Flint Bishop Limited | Professional & scientific | 2006 |
| Flint Bishop LLP | | 2006 |
| Flint Bishop Private Client Services Limited | Extraterritorial | 2022 |
| Flint Enterprises Limited | Professional & scientific | 2007 |
| Flintbrook Limited | Wholesale & retail | 1994 |
| Flints Direct Limited | Extraterritorial | 2006 |
| Flissie Limited | Wholesale & retail | 2021 |
| Floflo Global UK Ltd | Professional & scientific | 2025 |
| Floki Construction Ltd | Manufacturing | 2019 |
| Flokky Company Limited | Construction | 2018 |
| Flomotion Limited | Manufacturing | 2020 |
| Floor 2 Wall Limited | Manufacturing | 2002 |
| Flooring Marketplace Ltd | Wholesale & retail | 2026 |
| Floorpoint Ltd | Construction | 2026 |
| Floorstore (Stoke) Limited | Wholesale & retail | 2018 |
| Floperl Ltd | Health & social care | 2023 |
| Florence Jean 8990 Ltd | Other services | 2024 |
| Florentine Ltd | Hospitality | 2021 |
| Florin Nicolae Ltd | Transport & logistics | 2014 |
| Florina’S Flowers Ltd | Wholesale & retail | 2025 |
| Flourish Products UK Ltd | Wholesale & retail | 2026 |
| Flow & Shape Ltd | Professional & scientific | 2025 |
| Flow Community Services CIC | Financial services | 2025 |
| Flow Cyps Ltd | Health & social care | 2023 |
| Flow Healthcare Services Limited | Administrative & support | 2022 |
| Flow Homes Ltd. | Hospitality | 2023 |
| Flow Massage Ltd | Health & social care | 2024 |
| Flow Power Solutions Limited | Construction | 2019 |
| Flow Standard Ltd | Construction | 2026 |
| Flower Engineering Ltd | Manufacturing | 2017 |
| Flower From Daria Ltd | Wholesale & retail | 2023 |
| Flower Quality Solutions Limited | Wholesale & retail | 2021 |
| Flowerfield Properties Limited | Real estate | 2019 |
| Flowers Less Ordinary Limited | Wholesale & retail | 2023 |
| FLOWERS24 Ltd | Wholesale & retail | 2018 |
| Flowfloor Limited | Construction | 2017 |
| Flowgro Limited | Agriculture & fishing | 2016 |
| Flowjump Ltd | Hospitality | 2022 |
| Flowstate Ventures Ltd | Information & communication | 2021 |
| Fluent Property Ltd | Real estate | 2017 |
| Fluffy Piggy Ltd | Information & communication | 2025 |
| Fluid Digital Ideas Limited | Administrative & support | 2019 |
| Fluid Group (UK) Limited | Financial services | 2012 |
| Fluid Holdings Limited | Financial services | 2025 |
| Fluid Homes Ltd | Construction | 2025 |
| Fluid Ideas Limited | Professional & scientific | 2006 |
| Fluid Services (Northern) Limited | Professional & scientific | 1989 |
| Fluid Services (Southern) Limited | Professional & scientific | 1989 |
| Fluid Wash Ltd | Administrative & support | 2023 |
| Flux Legacy Limited | Professional & scientific | 2026 |
| FLX Technical Services Limited | Other services | 2024 |
| FLY Home Properties Ltd | Real estate | 2016 |
| Flyboi Ltd | Wholesale & retail | 2025 |
| Flying High Properties Ltd | Real estate | 2021 |
| Flying Nimbus Ltd | Professional & scientific | 2017 |
| Flynn Veterinary Neurology Ltd | Professional & scientific | 2023 |
| Flytec Ltd | Manufacturing | 2024 |
| FM Cornerstone Limited | Administrative & support | 2024 |
| FM Primary Care Ltd | Health & social care | 2026 |
| FM Tiles Limited | Wholesale & retail | 2024 |
| FMB Radio CIC | Manufacturing | 2019 |
| Fmco Ltd | Professional & scientific | 2019 |
| FMJ Limited | Manufacturing | 2023 |
| FN Midland Holdings Ltd | Financial services | 2024 |
| FNG Technologies Ltd | Information & communication | 2021 |
| FNK1LOGISTICS Limited | Transport & logistics | 2026 |
| Focus Coaching and Consulting Ltd | Professional & scientific | 2014 |
| Focus Consultants 2010 LLP | | 2010 |
| Focus Interior Contracts Limited | Construction | 1992 |
| Folie a Deux Limited | Professional & scientific | 2025 |
| Follex Construction Ltd | Construction | 2023 |
| Folvora Limited | Wholesale & retail | 2025 |
| Fomo Property Management Ltd | Real estate | 2025 |
| Fone Doctors Ltd | Wholesale & retail | 2024 |
| Fone Goods Limited | Manufacturing | 2021 |
| Fonegods Limited | Wholesale & retail | 2007 |
| Food & Dairy Engineering Co Limited | Manufacturing | 2000 |
| Food & Education Enterprise CIC | Hospitality | 2013 |
| Food Box Derby Limited | Hospitality | 2024 |
| Food Delivery Derby Ltd | Hospitality | 2019 |
| Food FAM Ltd | Hospitality | 2024 |
| Food Hygiene Consultants Ltd | Education | 2010 |
| Food Project & Development Services Limited | Administrative & support | 2005 |
| Food Project Services Limited | Hospitality | 2020 |
| Foodcom Ltd | Wholesale & retail | 2013 |
| Foodcore Limited | Hospitality | 2025 |
| Foodish by Donkariscatering Ltd | Hospitality | 2025 |