| First FIX Plumbers Limited | Construction | 2012 |
| First Glass Surrey Limited | Construction | 2012 |
| First Outsource Solutions Ltd | Administrative & support | 2023 |
| First Regent Securities Limited | Real estate | 2002 |
| Firth Brown Associates Limited | Professional & scientific | 2022 |
| Fiscus Global Advisors Limited | Professional & scientific | 2017 |
| Fisher Potatoes Limited | Wholesale & retail | 1983 |
| Fit With Frank Limited | Arts & recreation | 2018 |
| Fitbox Group Limited | Financial services | 2023 |
| Fitbox Personal Training Limited | Other services | 2014 |
| Fitzzi Ltd | Wholesale & retail | 2025 |
| Fivestar Properties & Developments Ltd | Construction | 2006 |
| Fixit Surface Repair Limited | Construction | 2018 |
| FJB Systems LLP | | 2003 |
| Flagship Drive Ltd. | Transport & logistics | 2017 |
| Flash Dragon Investments Ltd | Real estate | 2019 |
| Flattening the Curve Ltd | Professional & scientific | 2014 |
| Fleetwood Developments Limited | Real estate | 1983 |
| Fleetwood Investments Limited | Real estate | 2005 |
| Flex Lettings Ltd | Real estate | 2025 |
| Flexhomes Limited | Real estate | 2020 |
| Flexhomes Solutions Limited | Real estate | 2022 |
| Flightplanpro Ltd | Information & communication | 2010 |
| Flipchart Unlimited | Financial services | 2013 |
| FLO Consultants Limited | Real estate | 2010 |
| Float Productions Limited | Professional & scientific | 2008 |
| Flood Design Limited | Information & communication | 2007 |
| Floor Heating Solutions Limited | Construction | 2010 |
| Flooring Sales Limited | Administrative & support | 2004 |
| Florence Care Reading Limited | Health & social care | 2003 |
| Flourish Therapy Limited | Health & social care | 2023 |
| Flower Moon Ltd | Health & social care | 2023 |
| Flying Bears Ltd | Information & communication | 2019 |
| Flying Bulb Ltd | Professional & scientific | 2016 |
| Flyjama Ltd | Transport & logistics | 2018 |
| FM Cosmetics UK Ltd | Extraterritorial | 2007 |
| FM Future Limited | Professional & scientific | 2019 |
| FMC & Associates Limited | Professional & scientific | 2009 |
| FN Clinical Research Limited | Professional & scientific | 2016 |
| FNC (UK) Ltd | Professional & scientific | 2014 |
| Focap 2020 Limited | Energy | 2020 |
| Foley Four Consulting Ltd | Professional & scientific | 2024 |
| Foliorum Holding Ltd | Financial services | 2018 |
| Food Supply Packaging Ltd | Wholesale & retail | 2025 |
| Footcare Centre Weybridge Holdings Limited | Public administration | 2024 |
| Forbes Scott Law Limited | Administrative & support | 2025 |
| Forbesclaymore Construction Ltd | Construction | 2015 |
| Forbesclaymore London Ltd | Construction | 2022 |
| Foreman Ventures Limited | Professional & scientific | 2023 |
| Forest Hill Residents Limited | Households | 1985 |
| Forge Together Ltd | Professional & scientific | 2023 |
| Formatendure Limited | Information & communication | 1998 |
| Formidable Arts Limited | Information & communication | 2013 |
| Formula Women Limited | Professional & scientific | 2010 |
| Formulations Limited | Professional & scientific | 2006 |
| Fortitude Estate Management Limited | Real estate | 2024 |
| Forton Medical Services Ltd | Health & social care | 2018 |
| Fortune Grand Development (UK) Limited | Real estate | 2019 |
| Fortune Grand Investment Limited | Real estate | 2020 |
| Fortune Pacific Investment Limited | Real estate | 2024 |
| Forum Investments Limited | Real estate | 1975 |
| Forward Logistics (Middle East) Limited | Transport & logistics | 2007 |
| Fosters Consult Ltd | Professional & scientific | 2024 |
| Foundation Commerce Ltd. | Information & communication | 2014 |
| Foundation Property Marketing Limited | Administrative & support | 2024 |
| Four and One Ltd | Wholesale & retail | 2022 |
| Four Seasons Garden Care Ltd | Administrative & support | 2014 |
| Fourteen Graphic Design Limited | Professional & scientific | 2011 |
| Fourvenues UK Ltd | Information & communication | 2022 |
| FOX DEN Restaurants Limited | Hospitality | 2019 |
| FOX PI Limited | Real estate | 2015 |
| Foxhills Landscapes Limited | Administrative & support | 2019 |
| Foxlydiate Developments Limited | Professional & scientific | 1997 |
| Franceschi Cacao Trading Ltd | Wholesale & retail | 2020 |
| Franella Associates Limited | Financial services | 2019 |
| Frankenfish Ltd | Professional & scientific | 2023 |
| Franks Ventures Limited | Professional & scientific | 2018 |
| Frantschach Holdings UK Limited | Professional & scientific | 1977 |
| Fraser-Ferri Limited | Other services | 2021 |
| Frazer Music Ltd | Information & communication | 2026 |
| Fred Wilson Digital Limited | Education | 2018 |
| Fred Wilson Marine LLP | | 2018 |
| Freemademe Ltd | Other services | 2021 |
| Frelch Limited | Professional & scientific | 2011 |
| French Adventure Limited | Wholesale & retail | 1996 |
| Frepisa Holdings Limited | Administrative & support | 2019 |
| Freybors Ltd | Wholesale & retail | 2011 |
| Friday Social Limited | Professional & scientific | 2018 |
| From Nine to Thrive Ltd | Professional & scientific | 2020 |
| Fromson Construction Company Limited | Other services | 1993 |
| FRONT4 Limited | Administrative & support | 2000 |
| FRONT4 Music Limited | Arts & recreation | 2004 |
| Frost & Forest Ltd | Wholesale & retail | 2019 |
| Frost Fabrications Limited | Manufacturing | 2019 |
| Frosts Fireplaces Limited | Construction | 2012 |
| Fruity and the Beast Ltd | Manufacturing | 2022 |
| FSG Tech Ltd | Information & communication | 2023 |
| FSI [UK] Limited | Real estate | 1987 |
| Fssl Ltd | Information & communication | 2021 |
| Fuel Fusion Connect Ltd | Manufacturing | 2025 |