| FI Property Solutions Ltd | Real estate | 2017 |
| FI Protect Ltd | Financial services | 2015 |
| Fiber Wave Ltd | Construction | 2023 |
| Fife CON Limited | Financial services | 2016 |
| Fifty Sixty Seventy Ltd | Wholesale & retail | 2019 |
| Filipas Driving Academy Ltd | Administrative & support | 2013 |
| Final Touch (GB) Ltd | Administrative & support | 2001 |
| Final Touch Processing Limited | Administrative & support | 2002 |
| Financial Management Ltd | Professional & scientific | 2001 |
| Finatt Networks Limited | Information & communication | 2009 |
| Finchley Films Ltd | Extraterritorial | 2022 |
| Finchtrack Limited | Real estate | 2013 |
| Fine Foods Restaurants Ltd | Hospitality | 2019 |
| Finepoint Graphics Limited | Administrative & support | 2016 |
| Finest Fruits Ltd | Administrative & support | 2021 |
| Finmacrocosm Ltd | Information & communication | 2017 |
| Finstral UK Limited | Manufacturing | 2024 |
| Finterna Limited | Wholesale & retail | 2025 |
| Fintrain Ltd | Professional & scientific | 2021 |
| FIR Tree Court (Freehold) Limited | Real estate | 1998 |
| Fire Projects London Ltd | Construction | 2020 |
| Fire Stop Solutions Ltd | Administrative & support | 2015 |
| Fireaway Wembley Limited | Hospitality | 2023 |
| Firedon Ltd. | Public administration | 2007 |
| Firetribe Limited | Real estate | 2003 |
| Firetribe Properties Limited | Real estate | 2011 |
| Firion Limited | Professional & scientific | 2023 |
| Firmbase Developments Limited | Construction | 2015 |
| First Choice Cabling Ltd. | Information & communication | 2001 |
| First Choice Carpets and Beds Ltd | Wholesale & retail | 2011 |
| First Claremont Freehold Company Limited | Households | 2000 |
| First Contractors Ltd | Construction | 2017 |
| First E-Capital Ltd | Information & communication | 2002 |
| First FEW Weeks Limited | Information & communication | 2015 |
| First Home Real Estate Ltd | Construction | 2024 |
| First London Freeholds Ltd | Professional & scientific | 2015 |
| First Rodeo Ltd | Information & communication | 2018 |
| First Step Support Limited | Health & social care | 2025 |
| First Stop Fashion Limited | Wholesale & retail | 2018 |
| First Technology Investments Limited | Financial services | 2026 |
| First Waste Limited | Wholesale & retail | 2020 |
| First-Rate Fibre Limited | Information & communication | 2021 |
| Fiscalacts Accounting Services Ltd | Professional & scientific | 2025 |
| Fishnet Communications Limited | Administrative & support | 1998 |
| Fitgoals Ltd | Wholesale & retail | 2024 |
| Fitmibody Limited | Arts & recreation | 2015 |
| Fitzblin Design Ltd | Information & communication | 2021 |
| Fitzbourne Consultancy Limited | Real estate | 2018 |
| Fitzroy Hospitality Ltd | Hospitality | 2022 |
| Fitzwilliam Court Borehamwood Freehold Ltd | Real estate | 2012 |
| Five 7 Consulting Limited | Extraterritorial | 2014 |
| Five Minute Box (UK) Limited | Education | 2014 |
| Fixation Academy of Performing Arts Limited | Education | 2022 |
| Fixdirect Group Ltd. | Information & communication | 2009 |
| Fixitin Post - Freelance Post Production Network Ltd | Information & communication | 2026 |
| Fizz POP Holdings Ltd | Financial services | 2024 |
| Fizzy Liquid Ltd | Information & communication | 2012 |
| FJ Corp Services Ltd | Real estate | 2018 |
| FJ Corporation Ltd | Real estate | 2011 |
| FL TEN Ltd | Education | 2023 |
| FL Tiger Ltd | Information & communication | 2022 |
| FL19 CIC | Health & social care | 2020 |
| FL4 Bespoke Furniture Ltd | Wholesale & retail | 2025 |
| FL4 Group Ltd | Construction | 2020 |
| Flash Point Pictures Limited | Information & communication | 1995 |
| Flask Hill Advisory Ltd | Professional & scientific | 2024 |
| Flat 12, 42 Onslow Gardens Limited | Real estate | 2021 |
| Flat 4 Mancroft Limited | Real estate | 2020 |
| Flat E 22 Cleveland Square Limited | Real estate | 2022 |
| Flats at 4 Smith Street Limited | Real estate | 2013 |
| Flex Ceilings Limited | Manufacturing | 2022 |
| Flexiline Limited | Real estate | 1996 |
| Flight Training London Ltd | Transport & logistics | 2012 |
| Flodrive Garth Ltd | Real estate | 2015 |
| Floored IT! Ltd | Wholesale & retail | 2024 |
| Floorture Ltd | Professional & scientific | 2023 |
| Florin Rusu Ltd | Construction | 2016 |
| Floris Transport Limited | Transport & logistics | 2017 |
| Flow & Glow Plumbing Ltd | Construction | 2017 |
| Flowergate Management Company Limited | Households | 1995 |
| Flowers by Alina Limited | Other services | 2018 |
| Flowlab Studios UK Limited | Information & communication | 2022 |
| FLS Accounting Solutions Limited | Professional & scientific | 2015 |
| FLS Employees Trustees Limited | Extraterritorial | 2020 |
| FLY Dragon Contractor Limited | Construction | 2015 |
| FLY Elstree Ltd | Professional & scientific | 2010 |
| FLY YOU Fools Ltd | Professional & scientific | 2023 |
| FM Medico Limited | Health & social care | 2018 |
| Fnem Properties Ltd | Real estate | 2022 |
| Focus 4 People Limited | Professional & scientific | 2005 |
| Focus Academy Limited | Education | 2024 |
| Focus Beauty Limited | Other services | 2024 |
| Focus Cctv Limited | Other services | 2018 |
| Focus on Care Recruitment Limited | Administrative & support | 2000 |
| Focus Right Ltd | Wholesale & retail | 2016 |
| Foldcroft Logistics LLP | | 2016 |
| Follyvision Limited | Arts & recreation | 2016 |
| Fontis Property Management Limited | Real estate | 2004 |
| Food & FIN Ltd | Hospitality | 2026 |
| Food Containers Manufacturing UK Ltd | Manufacturing | 2008 |