| First Fair Cars Ltd | Transport & logistics | 2010 |
| First London Limited | Transport & logistics | 2025 |
| First Point Finance Ltd | Financial services | 2020 |
| First Step Advisors Ltd | Professional & scientific | 2025 |
| Fishele Limited | Extraterritorial | 2024 |
| Fishing Experience Limited | Wholesale & retail | 2020 |
| Fishland Ltd | Wholesale & retail | 2014 |
| Fismar Limited | Professional & scientific | 2023 |
| Fission Care Ltd | Health & social care | 2022 |
| Fit Litter UK Ltd | Wholesale & retail | 2024 |
| FIT1 Ltd | Wholesale & retail | 2016 |
| Fitness Groove & Joy Ltd | Arts & recreation | 2021 |
| Fitspine Physio Ltd | Health & social care | 2026 |
| Fitton Management Ltd | Professional & scientific | 2021 |
| Fitze Clinics Limited | Health & social care | 2017 |
| Five Star House Development Limited | Construction | 2022 |
| Five Star Real Properties Ltd | Real estate | 2023 |
| Fiwan Limited | Administrative & support | 2011 |
| FIX My Fone Ltd | Wholesale & retail | 2015 |
| Fixitnow Limited | Construction | 2025 |
| Fixlab Motors Ltd | Wholesale & retail | 2025 |
| FKM Clothes Limited | Wholesale & retail | 2024 |
| Flagstaff Communications Ltd | Professional & scientific | 2016 |
| Flame Charcoal House Ltd | Hospitality | 2019 |
| Flame Master Limited | Professional & scientific | 2023 |
| Flames of Love Ltd | Hospitality | 2024 |
| Flametree Capital Limited | Financial services | 2023 |
| Flamingo Housing Limited | Real estate | 2014 |
| Flamy Grill Limited | Hospitality | 2022 |
| Flash Beauty by DD Ltd | Other services | 2023 |
| Flash Recycle Ltd | Wholesale & retail | 2024 |
| Flashback LJ Films Productions Limited | Information & communication | 2020 |
| Flashfix Mobile and Computer Ltd | Wholesale & retail | 2024 |
| FLAT123 Ltd | Households | 2025 |
| Flavius Interiors Ltd | Construction | 2025 |
| Fleet Cars Private Hire Limited | Transport & logistics | 2020 |
| Fleet Taxi & Private Hire Limited | Transport & logistics | 2025 |
| Fleetlandia Limited | Professional & scientific | 2016 |
| Fleex Utilities Ltd | Construction | 2023 |
| Fleexone Utilities Ltd | Construction | 2026 |
| Flex Active Group Limited | Administrative & support | 2025 |
| Flexistaff Logistics Ltd | Transport & logistics | 2026 |
| Flexy Cars Ltd | Wholesale & retail | 2016 |
| Flight Dreams Limited | Administrative & support | 2025 |
| Flightpath Freehold Limited | Households | 2006 |
| Flights Dream Limited | Administrative & support | 2025 |
| Flima Limited | Professional & scientific | 2005 |
| Flipkart Ltd | Wholesale & retail | 2014 |
| Flippin' Cheese Aberdeen Ltd | Hospitality | 2019 |
| Flitking (Properties) Limited | Real estate | 2025 |
| Flitking Limited | Construction | 2021 |
| Flo-Right Guttering & Drainage Ltd | Other services | 2022 |
| Float Distribution Limited | Wholesale & retail | 2016 |
| Flora Commercial LRS Limited | Real estate | 2022 |
| Flora Freehold LRS Limited | Real estate | 2022 |
| Flora-Sky Limited | Professional & scientific | 2022 |
| Floreben Limited | Real estate | 2025 |
| Florence Adeline Ltd | Construction | 2021 |
| Flores DE LA Habana Ltd | Wholesale & retail | 2025 |
| Florin Lucescu Ltd | Construction | 2014 |
| Florin Vasile Ceclea Ltd | Construction | 2023 |
| Florplan Services Limited | Other services | 2004 |
| Flourish Careers Limited | Wholesale & retail | 2013 |
| Flower ME Ltd | Wholesale & retail | 2017 |
| Flower Paradise Ltd | Real estate | 2014 |
| Flukey Bros Investments Ltd | Administrative & support | 2023 |
| FLV Plumbing Services Ltd | Construction | 2017 |
| Flying Union Limited | Hospitality | 2024 |
| FM Cars & Spares Limited | Wholesale & retail | 2021 |
| Fmxa Limited | Professional & scientific | 2013 |
| FN Resources Limited | Administrative & support | 2014 |
| FND Property Solutions Ltd | Real estate | 2023 |
| Fnik Ltd | Professional & scientific | 2002 |
| Foamflower Limited | Professional & scientific | 2016 |
| Folgan Limited | Administrative & support | 2009 |
| Folio Film Productions Ltd | Information & communication | 2026 |
| Folkem Global Solutions Ltd | Information & communication | 2004 |
| Fomimat Limited | Wholesale & retail | 2020 |
| Fomro Limited | Professional & scientific | 2010 |
| Fone US Ayva Ltd | Wholesale & retail | 2025 |
| Fone US Edgware Ltd | Wholesale & retail | 2020 |
| Fonic Limited | Information & communication | 2004 |
| Fonic Music Limited | Information & communication | 2013 |
| Fontail Limited | Professional & scientific | 2008 |
| Food 4 Home Ltd | Manufacturing | 2026 |
| Food App Limited | Hospitality | 2023 |
| Food Delish Ltd | Hospitality | 2023 |
| Fooderia Enterprises Ltd | Manufacturing | 2014 |
| Foodhubb Ltd | Hospitality | 2024 |
| Foodie Haven Limited | Hospitality | 2024 |
| Foodrico Ltd | Wholesale & retail | 2025 |
| Footprints Surgery Limited | Health & social care | 2012 |
| FOR US by US Organisation | Hospitality | 2020 |
| FOR Your Eternity Ltd | Manufacturing | 2025 |
| Forburg Investments Limited | Extraterritorial | 2016 |
| Forbycroft Limited | Real estate | 2017 |
| Forced to Flee C.I.C. | Other services | 2026 |
| Foreland Court Property Management Co, Limited | Households | 1963 |
| Foresight Accounting Services Ltd | Professional & scientific | 2014 |
| Forest Dental Limited | Health & social care | 2021 |