| FCC Energy Limited | Administrative & support | 2018 |
| FCC Environment (Berkshire) Limited | Water & waste | 2005 |
| FCC Environment (Lincolnshire) Limited | Water & waste | 2010 |
| FCC Environment (UK) Limited | Administrative & support | 1994 |
| FCC Environment Developments Limited | Administrative & support | 2016 |
| FCC Environment Limited | Administrative & support | 1993 |
| FCC Environment Lostock Limited | Administrative & support | 2019 |
| FCC Environment Services (UK) Limited | Water & waste | 1989 |
| FCC LDF Limited | Real estate | 2023 |
| FCC Lostock Holdings Limited | Administrative & support | 2019 |
| FCC Movers Ltd | Transport & logistics | 2018 |
| FCC O&M Services Limited | Water & waste | 2011 |
| FCC PFI Holdings Limited | Administrative & support | 2005 |
| FCC Recycling (UK) Limited | Water & waste | 1991 |
| FCC Waste Management Limited | Water & waste | 1998 |
| FCC Waste Services (UK) Limited | Water & waste | 1970 |
| FCC Wrexham PFI (Phase II Holding) Limited | Administrative & support | 2012 |
| FCC Wrexham PFI (Phase II) Limited | Water & waste | 2012 |
| FCC Wrexham PFI Holdings Limited | Administrative & support | 2005 |
| FCC Wrexham PFI Limited | Water & waste | 2005 |
| Fcmo Limited | Financial services | 2022 |
| FCN Consulting Ltd | Health & social care | 2026 |
| Fconsult Ltd | Health & social care | 2022 |
| Fcsb Este Steaua Ltd | Transport & logistics | 2026 |
| Fd-Omp Ltd | Other services | 2009 |
| Fdac Express Ltd | Transport & logistics | 2024 |
| FDC Auto Ltd | Wholesale & retail | 2018 |
| FDM Projects Ltd | Construction | 2025 |
| FDP Services Ltd | Real estate | 2023 |
| Fearn Wood Flooring Limited | Administrative & support | 2003 |
| Feast 78 Ltd | Hospitality | 2022 |
| Feast at Bawtry Ltd | Hospitality | 2017 |
| Feast Treats Ltd | Hospitality | 2025 |
| Feastaway Ltd | Hospitality | 2023 |
| Feather Foot Developments Ltd | Real estate | 2019 |
| Feather Foot Group Holdings Limited | Financial services | 2024 |
| Feather Foot Holdings 2 Ltd | Financial services | 2022 |
| Feather Foot Holdings Ltd | Real estate | 2015 |
| Feather Foot Midco Limited | Financial services | 2024 |
| Featherfoot 2024 NO1 Limited | Financial services | 2024 |
| Featherfoot 2024 NO2 Limited | Financial services | 2024 |
| Featherfoot 21 Cleveland Limited | Financial services | 2021 |
| Featherfoot 24 Avenue Limited | Financial services | 2019 |
| Featherfoot Asset Holdings 1 Limited | Financial services | 2021 |
| Featherfoot Asset Holdings 2 Limited | Financial services | 2021 |
| Featherfoot Asset Holdings 3 Limited | Financial services | 2021 |
| Featherfoot Balance Limited | Financial services | 2021 |
| Featherfoot Bridge Leeds Limited | Financial services | 2021 |
| Featherfoot Britannia (Doncaster) Limited | Financial services | 2021 |
| Featherfoot Britannia (Hull) Limited | Financial services | 2021 |
| Featherfoot Britannia Limited | Financial services | 2019 |
| Featherfoot Capital Limited | Real estate | 2021 |
| Featherfoot CH Residential Limited | Financial services | 2024 |
| Featherfoot Charles House Limited | Financial services | 2020 |
| Featherfoot Churchside Residential Limited | Real estate | 2024 |
| Featherfoot Cleveland Limited | Financial services | 2019 |
| Featherfoot Coachman Limited | Financial services | 2021 |
| Featherfoot Consort Limited | Financial services | 2021 |
| Featherfoot Danum Limited | Financial services | 2019 |
| Featherfoot Exchange Limited | Financial services | 2019 |
| Featherfoot Glass Street Limited | Financial services | 2020 |
| Featherfoot Glenthorne Limited | Financial services | 2019 |
| Featherfoot Grosvenor House Limited | Financial services | 2021 |
| Featherfoot Kelham Limited | Financial services | 2019 |
| Featherfoot Lambert House Limited | Financial services | 2022 |
| Featherfoot Linacre Limited | Financial services | 2021 |
| Featherfoot Newspaper House Limited | Financial services | 2019 |
| Featherfoot Portland House Limited | Real estate | 2017 |
| Featherfoot Rawdon Holdings Limited | Real estate | 2021 |
| Featherfoot Rawdon Limited | Financial services | 2019 |
| Featherfoot York House Limited | Financial services | 2019 |
| Febe Ltd | Wholesale & retail | 2020 |
| Feed Worldwide Limited | Water & waste | 2013 |
| FEELIXX11 Ltd | Transport & logistics | 2025 |
| Feelyte Ltd | Wholesale & retail | 2023 |
| Feenstra Limited | Professional & scientific | 2021 |
| FEI Systems Ltd | Construction | 2024 |
| FEL Welding & Fabrication Ltd | Manufacturing | 2025 |
| Felder Delivery Ltd | Transport & logistics | 2019 |
| Felder Transport Ltd | Transport & logistics | 2024 |
| Felicity Healthcare Services Limited | Health & social care | 2019 |
| Fellas Barbers U.K. Ltd | Other services | 2020 |
| Fellowes Ltd | Manufacturing | 1965 |
| Fems Transport Ltd | Transport & logistics | 2015 |
| Fencing Solutions Northern Limited | Administrative & support | 2017 |
| Fenestra Build Limited | Information & communication | 2014 |
| Fenton Barnes Services Ltd | Administrative & support | 2025 |
| Fenton Barnes Support Ltd | Administrative & support | 2025 |
| Fenton TM Limited | Transport & logistics | 2016 |
| Fenwood House Limited | Other services | 2014 |
| Ferdy Enterprise Limited | Health & social care | 2016 |
| Ferens Property Trading Limited | Construction | 2016 |
| Fergelectrical Limited | Construction | 2022 |
| Fern Digital Group Ltd | Information & communication | 2021 |
| Ferncy Limited | Wholesale & retail | 2026 |
| Fernholme Development Ltd | Construction | 2026 |
| Fess Group Limited | Professional & scientific | 2019 |
| Fess Hire Ltd | Administrative & support | 2020 |
| Fess Holdings Limited | Financial services | 2024 |
| Fess Industries Ltd | Professional & scientific | 2023 |