| FEN Park Ltd | Real estate | 2021 |
| Fenestration Recycling Company Limited | Administrative & support | 2011 |
| Feng GU Ltd | Hospitality | 2026 |
| Fenix Plumbing & Heating Ltd | Construction | 2026 |
| Fenland Logistics (DM) Ltd | Other services | 2020 |
| Fenland Software Limited | Information & communication | 1997 |
| Fenlark Ltd | Information & communication | 2025 |
| Fenous Ltd | Hospitality | 2021 |
| Fenroc SW Limited | Real estate | 2020 |
| Fentons Limited | Health & social care | 2019 |
| Fenwick and Tilbrook Ltd | Manufacturing | 2016 |
| Ferfic | Financial services | 2021 |
| Ferigi Limited | Information & communication | 1994 |
| Ferman Murphy Limited | Professional & scientific | 2017 |
| Fermandy House Limited | Professional & scientific | 2018 |
| Fermor Limited | Information & communication | 2015 |
| FERNANDES94 Ltd | Transport & logistics | 2025 |
| Fernbank Therapeutic Community Ltd | Health & social care | 2016 |
| Fernbranch Limited | Real estate | 1988 |
| Ferngrove Property Maintenance Ltd | Construction | 2025 |
| Fernley Solutions Limited | Information & communication | 2013 |
| Ferrier Farrant Ltd | Construction | 2022 |
| Ferron Fabrications Limited | Manufacturing | 2003 |
| Ferryboat Felixstowe Limited | Hospitality | 2008 |
| Ferrygate Camping Ltd | Hospitality | 2024 |
| Festival MAG Ltd | Information & communication | 2014 |
| Festival of Food Limited | Real estate | 2009 |
| Fetal Monitoring Limited | Health & social care | 2018 |
| Fetch Associates Ltd | Administrative & support | 1998 |
| Fetch Ltd | Professional & scientific | 2017 |
| Fettle Cafe Ltd | Hospitality | 2016 |
| FEW Good MEN (East Anglia) CIC | Administrative & support | 2025 |
| FEW Good MEN Limited | Administrative & support | 2023 |
| Fewtrell Plumbing & Heating Ltd | Construction | 2021 |
| Fezzaanddel Limited | Manufacturing | 2019 |
| FF & Tree Planting Ltd | Wholesale & retail | 2023 |
| FF5533 Ltd | Professional & scientific | 2023 |
| FFG 2 Ltd | Financial services | 2023 |
| FFS (Transport) Ltd | Manufacturing | 2015 |
| FGS Networks Ltd | Information & communication | 2021 |
| FH LEE Properties Ltd | Real estate | 2024 |
| FHI Leasing Limited | Professional & scientific | 1985 |
| FHP Staff and Consultancy Ltd | Administrative & support | 2020 |
| Fiberweb Geosynthetics Limited | Manufacturing | 1981 |
| Fiberweb Holdings Limited | Manufacturing | 2006 |
| Fiberweb Limited | Manufacturing | 2006 |
| Fibreglass Solutions Ltd | Construction | 2022 |
| Fibretek Composites Ltd | Manufacturing | 2013 |
| Fictilis Limited | Real estate | 2020 |
| Fiction Ltd | Real estate | 2025 |
| Fiddys Butchers Ltd | Wholesale & retail | 2024 |
| Fidget Design Studios Limited | Professional & scientific | 2025 |
| Field & Tide Property Group Ltd | Construction | 2025 |
| Field News Limited | Wholesale & retail | 2018 |
| Field of Joy Ltd | Agriculture & fishing | 2021 |
| Field Security Services (UK) Limited | Real estate | 2007 |
| Field Support Services Group Limited | Administrative & support | 2016 |
| Fieldline Farms Ltd | Agriculture & fishing | 2018 |
| Fieldline Ltd | Construction | 2005 |
| Fieldmouse Property Limited | Real estate | 2025 |
| Fieldview Commercial Limited | Administrative & support | 2025 |
| Fiesta Take Away Limited | Hospitality | 2020 |
| Fifi's Handcrafted Ltd | Wholesale & retail | 2023 |
| Fifield Training Limited | Education | 2012 |
| Fifteeneightyfour Limited | Arts & recreation | 2003 |
| Fiftyeighth Ltd | Information & communication | 2023 |
| FIG Tree Homes Limited | Construction | 2024 |
| Fight Klub Franchising Limited | Arts & recreation | 2024 |
| Fight Klub Limited | Arts & recreation | 2016 |
| Figo 1989 Limited | Transport & logistics | 2018 |
| Figure in Motion Films Limited | Information & communication | 2026 |
| Film Kinetics Ltd | Information & communication | 2023 |
| Filsell Holdings Limited | Financial services | 2026 |
| Filterflow Limited | Other services | 2007 |
| Filterworld Limited | Manufacturing | 1995 |
| Final Frame Cinema Ltd | Information & communication | 2018 |
| Finance Partners Limited | Financial services | 2021 |
| Finance Transformation Success Ltd | Professional & scientific | 2012 |
| Financial Benefit Consultants Ltd | Financial services | 2024 |
| Financial in Veritate Business Ltd | Financial services | 2021 |
| Finbridge Global Ltd | Information & communication | 2023 |
| Finch Design Limited | Professional & scientific | 2021 |
| Fincham Bros Demolition Ltd | Construction | 2012 |
| FIND1 Ltd | Financial services | 2022 |
| Findafashion Trade Limited | Manufacturing | 2020 |
| Findatum Limited | Extraterritorial | 2021 |
| Findian CTO Services Ltd | Information & communication | 2012 |
| Finding Impact Ltd | Professional & scientific | 2018 |
| Finding the FUN Ltd | Information & communication | 2024 |
| Fine City Beer Co. Ltd | Manufacturing | 2025 |
| Fine City Events Ltd | Administrative & support | 2025 |
| Fine City Living Ltd | Real estate | 2026 |
| Fine City Ltd | Construction | 2021 |
| Fine City Properties LLP | | 2004 |
| Fine City Scaffolding Limited | Construction | 2021 |
| Fine City Testing Ltd | Information & communication | 2021 |
| Fine Dine 2019 Ltd | Hospitality | 2019 |
| Fine Edge Furniture Ltd | Manufacturing | 2011 |
| Fine Finishes Limited | Construction | 2019 |
| Fine Golf Collective Ltd | Wholesale & retail | 2018 |