| Filipino Nanny Housekeeper Carer Limited | Health & social care | 2021 |
| Film & Digital Ltd | Professional & scientific | 2020 |
| Film & TV SET Ltd | Construction | 2016 |
| Filmbook Limited | Information & communication | 2016 |
| Filmvision Limited | Administrative & support | 1997 |
| Filzerq Limited | Information & communication | 2005 |
| FIN Space Limited | Administrative & support | 2018 |
| Final Inspector Limited | Real estate | 2001 |
| Final Start Limited | Real estate | 2001 |
| Finance Divine Ltd | Professional & scientific | 2022 |
| Finance Matters for Schools Limited | Professional & scientific | 2011 |
| Finbridge Limited | Professional & scientific | 1995 |
| Fincasal Ltd | Extraterritorial | 2015 |
| Finch International Limited | Wholesale & retail | 2021 |
| Finchley Nurseries Limited | Wholesale & retail | 1929 |
| Fine & Country Automotive Limited | Wholesale & retail | 2021 |
| Fine Food Lands Ltd | Professional & scientific | 2019 |
| Fine Food Service Limited | Hospitality | 2019 |
| Fine Home Cleaning Service Ltd | Administrative & support | 2025 |
| Fine Line Decor Ltd | Construction | 2025 |
| Finecall Property Investments Limited | Real estate | 2023 |
| Fineit Solutions Limited | Information & communication | 2002 |
| Finetel Finance Limited | Financial services | 2005 |
| Finlay Estates Limited | Households | 2014 |
| Finlit Consultants UK Limited | Professional & scientific | 2024 |
| Finn Property Investments Limited | Real estate | 2009 |
| Finn Search Limited | Administrative & support | 2020 |
| Finsbury Clinical Limited | Health & social care | 2025 |
| Finsbury Construction Ltd | Construction | 2017 |
| Finspiria Partners Limited | Financial services | 2016 |
| Fintech Brokers Ltd | Financial services | 2025 |
| Fiona Bulmer Writing Services Limited | Professional & scientific | 2012 |
| Fiona Leahy Limited | Administrative & support | 2008 |
| Fiori Enterprises Ltd | Wholesale & retail | 2021 |
| Fire & Security Manager Ltd | Administrative & support | 2017 |
| Firefox Limited | Extraterritorial | 2009 |
| Firestone Protection Limited | Construction | 2023 |
| Firesure Ltd | Construction | 2022 |
| First (Emergency) Couriers Limited | Transport & logistics | 1991 |
| First Block Management Ltd | Households | 2025 |
| First Business Development Ltd | Professional & scientific | 2018 |
| First Choice Pharma Ltd | Administrative & support | 2006 |
| First Choice Rental Ltd | Administrative & support | 2019 |
| First Gainsborough Court Management Co. Limited | Households | 1988 |
| First Maltings Management Company Limited | Households | 1984 |
| First Practice Limited | Health & social care | 2023 |
| First Security Limited | Construction | 2007 |
| First Stop Roofing and Building Ltd | Construction | 2025 |
| First Vehicle Management Ltd. | Administrative & support | 2011 |
| Firstline Solutions Limited | Manufacturing | 2023 |
| Firstpride Limited | Manufacturing | 1997 |
| Fis-Edproperties Ltd | Real estate | 2016 |
| Fis-Edsolutions Ltd | Professional & scientific | 2011 |
| Fish Delight Ltd | Real estate | 2014 |
| Fish Fryer Ltd | Hospitality | 2024 |
| Fish Master Ltd | Hospitality | 2014 |
| Fishermans Catch Ltd | Hospitality | 2014 |
| Fit Habit Ltd | Arts & recreation | 2017 |
| Fit OUT Projects Ltd | Professional & scientific | 2019 |
| Fitch Taylor Johnson Ltd | Households | 2021 |
| Fitzgerald & Burke Builders Merchants Limited | Wholesale & retail | 1991 |
| Fitzrovia Footwear Ltd | Other services | 2022 |
| Five Nine Mechanical Limited | Construction | 2026 |
| Five Star Transportations Ltd | Transport & logistics | 2017 |
| FIX My Smile Ltd | Information & communication | 2019 |
| FJM Properties Limited | Real estate | 2020 |
| Flabbergasted Ltd | Professional & scientific | 2013 |
| Flamboycent Limited | Information & communication | 2025 |
| Flame Plumbing and Heating Limited | Construction | 2017 |
| Flash POP Sizzle Ltd | Arts & recreation | 2018 |
| Flat 1 Warwick RD Properties Ltd | Real estate | 2025 |
| Flat 2 Warwick RD Properties Ltd | Real estate | 2025 |
| Flatinvest Limited | Households | 1984 |
| Flatt and Houseman Limited | Administrative & support | 2020 |
| Flatwise Space Ltd | Construction | 2023 |
| Flawless Painters and Decorators Ltd | Construction | 2018 |
| FLB Industries Ltd | Hospitality | 2024 |
| Flexfit Coaching Ltd | Arts & recreation | 2025 |
| Flexible Resourcer Ltd. | Professional & scientific | 2014 |
| Flexology by Daniela Ltd | Health & social care | 2025 |
| Flexserve Resource Ltd | Administrative & support | 2014 |
| Flexserve UK Limited | Health & social care | 2009 |
| Flickerwick Limited | Wholesale & retail | 2019 |
| Flight Four Limited | Real estate | 2014 |
| Flim Studios Limited | Administrative & support | 2025 |
| Flip & Sear Holdings Ltd | Hospitality | 2024 |
| Flip & Sear Ilford Ltd | Hospitality | 2026 |
| Flip & Sear London City Ltd | Hospitality | 2024 |
| Flip & Sear Ltd | Hospitality | 2019 |
| Flipping Marvellous Properties Limited | Real estate | 2016 |
| Flocopia Limited | Information & communication | 2010 |
| Floorable Limited | Construction | 2017 |
| Floreal Ltd | Hospitality | 2021 |
| Floreat Aviation Capital Limited | Professional & scientific | 2019 |
| Floreat Capital Markets Limited | Professional & scientific | 2013 |
| Floreat Holding Limited | Financial services | 2013 |
| Floreat House Limited | Real estate | 2015 |
| Floreat Merchant Banking Limited | Professional & scientific | 2008 |
| Floreat Principal Investing Limited | Professional & scientific | 2015 |
| Floreat Private Limited | Professional & scientific | 2014 |