| FD2 Ltd | Professional & scientific | 2012 |
| FDH Aero Ltd | Manufacturing | 2013 |
| Feather & Brick Properties Ltd | Real estate | 2025 |
| Febran Limited | Real estate | 2002 |
| FED MAC Limited | Real estate | 2012 |
| Federato Technologies UK Ltd | Information & communication | 2025 |
| Feet at Macclesfield Ltd | Health & social care | 2010 |
| FEI DA Group Limited | Real estate | 2013 |
| FEI UK Limited | Manufacturing | 1989 |
| Felixstowe Logistic Solutions Ltd | Transport & logistics | 2009 |
| Fellpath Ltd | Professional & scientific | 2021 |
| Femfluence Limited | Other services | 2024 |
| Fenham Carr Limited | Financial services | 2025 |
| Fenix Interiors Ltd | Extraterritorial | 2021 |
| Ferenc Property Limited | Real estate | 2017 |
| Fernlea Advisory Limited | Professional & scientific | 2021 |
| Fernleigh House Management Company Limited | Households | 2020 |
| Ferrious Limited | Wholesale & retail | 2000 |
| Festival Construction Limited | Construction | 1988 |
| FEU Candles Ltd | Manufacturing | 2020 |
| FFB Group Ltd | Professional & scientific | 2022 |
| Ffhz Holding Ltd | Financial services | 2026 |
| Ffhz One Limited | Real estate | 2026 |
| FG Surgery Ltd | Health & social care | 2021 |
| FH England LLP | | 2006 |
| Fibre Revolution Holdings Ltd | Manufacturing | 2021 |
| Fibrelite (South) Limited | Professional & scientific | 1996 |
| FIC Shareco Limited | Wholesale & retail | 2004 |
| Fiduciaryplus Ltd | Professional & scientific | 2020 |
| Field Design & Build Ltd | Construction | 2007 |
| Fieldsman Management Limited | Extraterritorial | 1991 |
| Fieldtech Consulting Ltd | Manufacturing | 2024 |
| Fierce Rose Ltd | Information & communication | 2023 |
| Fillet Limited | Information & communication | 2007 |
| Film Cuisine Limited | Hospitality | 1994 |
| Filmbox Ltd | Wholesale & retail | 2025 |
| Filson Health LLP | | 2023 |
| Filtermech Holdings Limited | Professional & scientific | 2007 |
| FIM Holdings Limited | Financial services | 2019 |
| Final CUT Carpentry Productions Ltd | Manufacturing | 2023 |
| Final Third Operations Ltd | Professional & scientific | 2025 |
| Final TIE 2020 Ltd | Professional & scientific | 2020 |
| Finaldose Ltd | Professional & scientific | 2025 |
| Finance Care Service Limited | Financial services | 2019 |
| Finance Consultancy Limited | Professional & scientific | 2018 |
| Financeaas Ltd | Information & communication | 2017 |
| Financial Edge Holding Co Limited | Information & communication | 2018 |
| Financial Edge Training Limited | Information & communication | 2016 |
| Financial Management 5OLUTIONS Limited | Professional & scientific | 2026 |
| Finanstone LLP | | 2018 |
| Fination Ltd | Professional & scientific | 2023 |
| Finb Limited | Professional & scientific | 2011 |
| Finch Bakery Limited | Hospitality | 2019 |
| Finchmill Properties Limited | Real estate | 2018 |
| Fincovered LP | | 2021 |
| Findcoder Limited | Information & communication | 2012 |
| Finders Keepers Limited | Professional & scientific | 1977 |
| Findmyballs.Golf Limited | Wholesale & retail | 2025 |
| Findtransfers Ltd | Information & communication | 2012 |
| Fine Art AF Limited | Arts & recreation | 2025 |
| Fine Form Aesthetics Ltd | Health & social care | 2021 |
| Finedge Consulting Limited | Professional & scientific | 2023 |
| Fineline Balustrades Limited | Manufacturing | 2003 |
| Finesky Limited | Construction | 2020 |
| Finham Consulting Limited | Professional & scientific | 2017 |
| Finnvestments Limited | Professional & scientific | 2026 |
| Finspire Group Ltd | Financial services | 2025 |
| Finsup Technology Limited | Professional & scientific | 2024 |
| Fintech Calling Ltd | Professional & scientific | 2018 |
| Fintech Partners Ltd | Financial services | 2017 |
| Fiona Lavin Limited | Other services | 2014 |
| Fiona Mckay Limited | Administrative & support | 2016 |
| Fiona-Rose Limited | Professional & scientific | 1971 |
| Firbank Classics Limited | Wholesale & retail | 2000 |
| Firdale Construction Limited | Construction | 2006 |
| Firdale Plant Ltd | Administrative & support | 2018 |
| Fire & Safety Management (UK) Limited | Administrative & support | 2007 |
| Firebird Research Ltd | Professional & scientific | 2024 |
| Firecon Limited | Public administration | 2023 |
| Firelight Lighting Limited | Wholesale & retail | 2016 |
| Fireye UK Acquire Co. Limited | Financial services | 2026 |
| Firmbuild Limited | Wholesale & retail | 1987 |
| First Class Consultancy Limited | Professional & scientific | 2023 |
| First Direct Finance Limited | Real estate | 2006 |
| First Elite Ltd | Administrative & support | 2009 |
| First House Homes Ltd | Construction | 2012 |
| First Internet Marketing Limited | Information & communication | 2000 |
| First Personal Injury (UK) Limited | Professional & scientific | 2008 |
| First Personal Injury LLP | | 2011 |
| First Point Money Limited | Financial services | 2024 |
| Fish Finger Merch Limited | Wholesale & retail | 2020 |
| Fisher Clinical Services UK Limited | Administrative & support | 2004 |
| Fisher Maybridge Holdings Limited | Professional & scientific | 2002 |
| Fisher Scientific Holding U.K., Limited | Professional & scientific | 1994 |
| Fisher Scientific Oxoid Holdings Ltd | Professional & scientific | 2005 |
| Fisher Scientific UK Holding Company 2 | Professional & scientific | 2000 |
| Fisher Scientific UK Holding Company Limited | Professional & scientific | 2000 |
| Fisherbeck Management Limited | Hospitality | 1982 |
| Fissara Holdings Limited | Information & communication | 2014 |
| Fissara Limited | Extraterritorial | 2023 |