| FAB Communications Limited | Professional & scientific | 2017 |
| Fabz Steelwork Ltd | Manufacturing | 2026 |
| Facade External Solutions Limited | Construction | 2009 |
| Face Invest Limited | Health & social care | 2015 |
| Facemed Limited | Health & social care | 2008 |
| Fairfield Developments (Brentwood) Limited | Extraterritorial | 2014 |
| Fairview Crescent Management Company Limited | Households | 2020 |
| Fairview Storage Limited | Transport & logistics | 2007 |
| Fairway Developments London Limited | Real estate | 2019 |
| Fairway Properties (Essex) Ltd | Households | 2026 |
| Falcon Blast Ltd | Manufacturing | 2014 |
| Falcon MOT & Service Centre Limited | Wholesale & retail | 2018 |
| Falkus Limited | Manufacturing | 2012 |
| Fants Real Estate Limited | Administrative & support | 2003 |
| Fantz Limited | Administrative & support | 2014 |
| FAR East (Freight Agencies) Limited | | 1986 |
| Faraday PAY Contracts Limited | Professional & scientific | 2022 |
| Farina Management Limited | Professional & scientific | 2022 |
| Farmview Eggs Limited | Wholesale & retail | 2009 |
| Fast Key Services Limited | Manufacturing | 1996 |
| Fast Mechanic Services Ltd | Wholesale & retail | 2026 |
| FCH Illustrations Ltd | Arts & recreation | 2021 |
| Feather and Fibre UK Ltd | Manufacturing | 2004 |
| FED and ZED Transport Ltd | Transport & logistics | 2025 |
| Fellas Hair Ltd | Other services | 2002 |
| Femex Intelligent Transport Solutions Limited | Financial services | 2016 |
| Fencar Holdings Limited | Financial services | 2026 |
| Fencing Supplies London Ltd | Wholesale & retail | 2024 |
| Ferngie Limited | Administrative & support | 2004 |
| Fewc Property Services Ltd | Professional & scientific | 2026 |
| Fibre Clear Analytical Ltd | Professional & scientific | 2018 |
| Fida Motors Limited | Wholesale & retail | 2019 |
| Fidentia Advisory Limited | Professional & scientific | 2023 |
| Fidentia Technology Limited | Information & communication | 2026 |
| Fidget Investments Limited | Wholesale & retail | 2016 |
| Fidvest Ltd | Professional & scientific | 2026 |
| Field Motorsport Limited | Manufacturing | 2001 |
| Fiesta Consultancy Limited | Professional & scientific | 2017 |
| Fifit Training Limited | Arts & recreation | 2024 |
| Fimbo Limited | Administrative & support | 2004 |
| Final Fit OUT Ltd | Construction | 2026 |
| Financial Alan Limited | Professional & scientific | 1999 |
| FINANCIALINSIGHTS4U Limited | Professional & scientific | 2020 |
| Finely Tuned Physiotherapy Limited | Health & social care | 2013 |
| Finstick Limited | Administrative & support | 2005 |
| Fintech London Limited | Professional & scientific | 2017 |
| First Group Corporation Ltd | Health & social care | 2024 |
| First Manor Court Management Company Limited | Households | 1985 |
| Fish Tales Swim School Ltd | Education | 2023 |
| FISH4FLIES Limited | Wholesale & retail | 2005 |
| Fisher Commerce Ltd | Wholesale & retail | 2023 |
| Fishermans Friends LLP | | 2026 |
| Fit Floorings Limited | Construction | 2024 |
| Five Child Holdings Limited | Financial services | 2025 |
| Fiveteam Limited | Professional & scientific | 2002 |
| Fixco Construction Limited | Construction | 2024 |
| Fizzy Publishing Limited | Information & communication | 2022 |
| FJN Property Ltd | Real estate | 2026 |
| Flawless Taping Ltd | Construction | 2019 |
| Fleet Gymnastics Limited | Arts & recreation | 2018 |
| Fleet Maintenance Services Limited | Administrative & support | 2024 |
| Fleet Services Wickford Limited | Wholesale & retail | 2024 |
| Fleet Street's Finest Ltd. | Wholesale & retail | 2016 |
| Flex & Fold Studio Ltd | Health & social care | 2025 |
| Flirty Lashes Ltd | Other services | 2019 |
| Flourish Horse Health Ltd | Manufacturing | 2018 |
| Flowers by Fats Ltd | Wholesale & retail | 2023 |
| Flump Studio Ltd | Professional & scientific | 2015 |
| Flush Fit Ltd | Construction | 2025 |
| FNX Bathrooms Ltd | Wholesale & retail | 1999 |
| Focus Print & Publishing Ltd | Manufacturing | 2018 |
| FOG and Carter Ltd | Information & communication | 2024 |
| Folio Group Properties Ltd | Real estate | 2023 |
| Folio Group Solutions Ltd | Information & communication | 2023 |
| Food Mania (UK) Limited | Hospitality | 2013 |
| Foogi Limited | Administrative & support | 2001 |
| Football Business Services Limited | Professional & scientific | 2026 |
| Football Business Solutions Limited | Professional & scientific | 2026 |
| Force 4 Design Limited | Construction | 2003 |
| Foresters Tree Service Limited | Agriculture & fishing | 2017 |
| Forjo Care Ltd | Extraterritorial | 2024 |
| Fork Truck Direct Limited | Administrative & support | 2000 |
| Forktrucks.Com Limited | Information & communication | 2000 |
| Format Scaffolding Limited | Construction | 2019 |
| Forte Spectrum Ltd | Transport & logistics | 2026 |
| Fortis Engineering Limited | Professional & scientific | 2013 |
| Fortress Aluminium Holdings Limited | Financial services | 2024 |
| Fortress Aluminium Limited | Manufacturing | 2008 |
| Fortune Marketing Limited | Information & communication | 2003 |
| Forum Construction Limited | Construction | 2009 |
| Forum Contracts Limited | Construction | 2004 |
| Four Eyes Film Limited | Information & communication | 2016 |
| Four Notes Limited | Manufacturing | 2016 |
| Four Oaks Place Ltd | Households | 2020 |
| Four Piece Band LLP | | 2008 |
| Four Wheel Traction Limited | Professional & scientific | 1965 |
| Fourdragons Enterprise Limited | Construction | 2019 |
| FOX & Firkin Countryside Pubs Limited | Hospitality | 2024 |
| Foxgloves Associates Limited | Extraterritorial | 2010 |
| Foxhatch AB Ltd | Professional & scientific | 2024 |