| Fishingtripper Ltd | Arts & recreation | 2025 |
| Fistral Impex Limited | Other services | 1975 |
| Five Besbury Limited | Professional & scientific | 2019 |
| Fixd. Ltd | Construction | 2024 |
| Flagstaff Advisory Limited | Professional & scientific | 2024 |
| Flagstone Projects Limited | Construction | 2018 |
| Flavour Fantasy Ltd | Hospitality | 2025 |
| Fleur-De-Lys Widdington Limited | Hospitality | 2023 |
| Flight Performance Training Ltd | Administrative & support | 2017 |
| Flint Industrial Space Limited | Administrative & support | 2023 |
| Flint Office Group Limited | Administrative & support | 2021 |
| Flint Office Lite Ltd | Administrative & support | 2022 |
| Flint Office Space Ltd | Administrative & support | 2023 |
| Floormark Limited | Administrative & support | 2010 |
| Florence Marble (UK) Limited | Real estate | 2017 |
| Flower Grade Ltd | Extraterritorial | 2022 |
| Fluid Cube Limited | Professional & scientific | 2014 |
| FLY Festival CIC | Arts & recreation | 2025 |
| FLY INK Saffron Walden Ltd | Arts & recreation | 2024 |
| Flying Saucer Productions Limited | Information & communication | 2024 |
| FO Lakeside Limited | Arts & recreation | 2026 |
| FO Leisure Ltd | Arts & recreation | 2017 |
| Folgate Advisors Ltd | Professional & scientific | 2024 |
| Folies of Stansted Ltd | Wholesale & retail | 2021 |
| Follis Investments Limited | Construction | 1955 |
| Forbes Surveyors Ltd | Professional & scientific | 2013 |
| Force 36 Limited | Information & communication | 2002 |
| Ford Homes Limited | Construction | 2015 |
| Ford Homes Property Limited | Real estate | 2021 |
| Ford Homes Scaffolding Ltd | Construction | 2021 |
| Foresite Group Holdings Ltd | Extraterritorial | 2024 |
| Forest Fleece Ltd | Manufacturing | 2013 |
| Form Limited | Extraterritorial | 2000 |
| Formula 21 Limited | Professional & scientific | 2025 |
| Foster Family Holdings Ltd | Financial services | 2024 |
| Foster Williams Limited | Real estate | 2016 |
| Foto Theme Limited | Professional & scientific | 2008 |
| FOX & Associates Ltd | Administrative & support | 2025 |
| FOX Hall Investments Limited | Real estate | 2015 |
| Foxbank Limited | Wholesale & retail | 2003 |
| Foxglove Life Sciences Ltd | Professional & scientific | 2023 |
| Foxjax Limited | Information & communication | 2022 |
| Fractional CMO Consulting Limited | Professional & scientific | 2025 |
| FRAM3D Marketing Solutions Ltd | Professional & scientific | 2024 |
| Frambury Digital Ltd | Professional & scientific | 2026 |
| Frame and Fold Studio Limited | Professional & scientific | 2025 |
| Frame Stock Limited | Administrative & support | 2021 |
| Frameable Moments Limited | Wholesale & retail | 2026 |
| Frameshift Limited | Administrative & support | 2024 |
| Frances Hall Interiors Limited | Professional & scientific | 2026 |
| Frances Mary Rose Holdings Limited | Financial services | 2026 |
| Frances Mary Rose Ltd | Professional & scientific | 2013 |
| Frank Riccio Limited | Other services | 2016 |
| Freckle Media Ltd | Financial services | 2026 |
| Free World Enterprises Ltd | Professional & scientific | 2022 |
| Freedown Limited | Wholesale & retail | 2004 |
| Freeley Renewables Ltd | Construction | 2023 |
| Freeman Asset Management Ltd | Administrative & support | 2024 |
| Freeman Services Ltd | Professional & scientific | 2018 |
| Fresh and Frank Consulting Ltd | Professional & scientific | 2010 |
| Fresh Coats Painting and Plastering Ltd | Construction | 2023 |
| Freyen Limited | Transport & logistics | 2019 |
| Freygo Logistics Ltd | Transport & logistics | 2023 |
| Frontier Performance Limited | Information & communication | 2026 |
| Frontiere Medicale Holdings Limited | Professional & scientific | 2022 |
| Frontline Referrals Ltd | Information & communication | 2021 |
| Frontmed Consulting Limited | Professional & scientific | 2014 |
| Frontmed Trading Limited | Professional & scientific | 2013 |
| Frontside Property Limited | Administrative & support | 2013 |
| FUSED7 Ltd | Professional & scientific | 2012 |
| Future 30 Global Ltd | Financial services | 2021 |
| Future Ventures Ltd | Professional & scientific | 2022 |
| FV Limited | Extraterritorial | 2008 |
| FXT Properties Limited | Arts & recreation | 2011 |
| Fytobooster UK Ltd | Manufacturing | 2019 |
| G & a Consultancy Ltd | Professional & scientific | 2023 |
| G & I Reilly Property Management Ltd | Real estate | 2021 |
| G Alexander Building Services Limited | Construction | 2018 |
| G E & M Duke LLP | | 2011 |
| G J Hamilton Farms Limited | Agriculture & fishing | 1995 |
| G.A. Wisbey & SON Limited | Agriculture & fishing | 1964 |
| G.D.Culpin, Vintage Motor & Engineering Co Ltd | Wholesale & retail | 2021 |
| G.R. Smith (Thriplow) Limited | Agriculture & fishing | 1955 |
| G10 for MEN Beard and Grooming Products Ltd | Wholesale & retail | 2024 |
| GAK Property Management Limited | Real estate | 2021 |
| Gallagher Construction Limited | Extraterritorial | 1991 |
| Garbmann Ltd | Wholesale & retail | 2012 |
| Gardening for Kids Ltd. | Wholesale & retail | 2015 |
| Garson's Group Limited | Administrative & support | 2019 |
| Gates and Accessories Limited | Extraterritorial | 2015 |
| Gawm Solutions Limited | Professional & scientific | 2012 |
| GC 1971 Ltd | Administrative & support | 2010 |
| GCS Associates (UK) Ltd | Information & communication | 2013 |
| GDC 2025 Ltd | Professional & scientific | 2025 |
| Geddings Manor Farming Limited | Agriculture & fishing | 2017 |
| Gemjay Investments Limited | Administrative & support | 2017 |
| Gemstone Legal Limited | Professional & scientific | 2019 |
| Generation Alfa Limited | Financial services | 2013 |
| Genesis Precision Engineering Limited | Manufacturing | 2001 |
| Genome Research Limited | Professional & scientific | 1992 |