| Express Goods Ltd | Wholesale & retail | 2025 |
| Extra Curricular Sports Activities Ltd | Arts & recreation | 1998 |
| Eyeforai Ltd | Professional & scientific | 2025 |
| EZI Stride Ltd | Wholesale & retail | 2026 |
| EZK Development Limited | Construction | 2025 |
| F & M Automatic Amusement Machines Limited | Arts & recreation | 1975 |
| F F Cladding Limited | Construction | 2013 |
| F&B Studio Ltd | Professional & scientific | 2022 |
| F&M Topco Limited | Financial services | 2024 |
| F&S Book Keeping Ltd | Professional & scientific | 2012 |
| F&Z DRY Cleaners Ltd | Other services | 2024 |
| F-24 UK Limited | Information & communication | 2004 |
| Fabric Owls Limited | Manufacturing | 2023 |
| Facelift Academy Limited | Wholesale & retail | 2024 |
| Facelift Contracts Croxley Limited | Other services | 2022 |
| Facelift Interiors Croxley Ltd | Other services | 2022 |
| Fairoze Limited | Health & social care | 2013 |
| Falcon Grab & Haulage Limited | Administrative & support | 2017 |
| Falcon Holdings Limited | Financial services | 1920 |
| Fallon Formwork Limited | Construction | 2010 |
| Fanengine Holdings Ltd | Information & communication | 2026 |
| Fantasypro Ltd | Professional & scientific | 2023 |
| Farerio Cartio Ltd | Wholesale & retail | 2026 |
| Farid Properties Limited | Real estate | 2008 |
| Farm House Pizza Rickmansworth Limited | Hospitality | 2016 |
| Farma Consultancy Limited | Professional & scientific | 2023 |
| Farnham Joinery London Limited | Manufacturing | 2014 |
| Farrlyn Property Limited | Real estate | 2025 |
| Farrs Mews Management Company Limited | Real estate | 2015 |
| Fasaj Group Ltd | Wholesale & retail | 2018 |
| Fast Feast Foods Ltd | Hospitality | 2024 |
| Faygrace Ltd | Real estate | 2025 |
| Fbclinic Limited | Other services | 2018 |
| Felden Properties Ltd | Real estate | 2025 |
| Feline Quanta Ltd | Other services | 2017 |
| Fenchurch Holdings Ltd | Real estate | 2025 |
| Fern & Foam Limited | Hospitality | 2024 |
| FHT Brothers Ltd | Real estate | 2024 |
| Fields Electrical Consultancy Limited | Professional & scientific | 2016 |
| Fiets Limited | Professional & scientific | 2023 |
| Filotimo Limited | Hospitality | 2024 |
| Fina Glass Limited | Construction | 2014 |
| Final Duties Limited | Other services | 2008 |
| Finan Enterprises Limited | Wholesale & retail | 2015 |
| Financial Analysis & Accounting Services Ltd. | Professional & scientific | 2018 |
| Finch Interiors Limited | Professional & scientific | 2014 |
| Find Tiler Ltd | Professional & scientific | 2021 |
| Finding Eudaimonia Ltd | Health & social care | 2024 |
| Fine Events Limited | Professional & scientific | 2020 |
| Fintech Global Consultancy Ltd | Administrative & support | 2008 |
| Fintegrity Consulting Ltd | Professional & scientific | 2024 |
| Fireanswers Limited | Professional & scientific | 2016 |
| Firefox Web Solutions Ltd | Information & communication | 2017 |
| First Thought Accountancy Ltd | Professional & scientific | 2014 |
| First Thought Financial Limited | Financial services | 2022 |
| First Thought Financial Services Ltd | Financial services | 2018 |
| Fit-Tech London Ltd | Manufacturing | 2020 |
| Fitwell Studios Limited | Health & social care | 2014 |
| Five Star Punjab Traders Limited | Wholesale & retail | 2023 |
| Fixit Maintenance Limited | Administrative & support | 2017 |
| FK Manor Road Ltd | Real estate | 2022 |
| Flalmy Limited | Professional & scientific | 2021 |
| Flaming Silver Investments Limited | Financial services | 2019 |
| Flatsatsixteenchurchfield Limited | Real estate | 2022 |
| Fleet Accident Management Hub Limited | Administrative & support | 2025 |
| Fletcher Holdings Ltd | Financial services | 2016 |
| Flexible Consulting Limited | Professional & scientific | 2018 |
| Flint Management Ltd | Extraterritorial | 2008 |
| Flood Resilience & Remediation Consultants Ltd | Construction | 2012 |
| Flow LLP | | 2024 |
| Flowgrade Limited | Real estate | 1990 |
| FLY100 Ltd | Education | 2025 |
| Flying Corporation (Europe) Ltd | Arts & recreation | 2012 |
| Fmpurpose Limited | Administrative & support | 2016 |
| Focus 360 Ltd | Other services | 2022 |
| Focus on Fungus Ltd | Manufacturing | 2025 |
| Fohera Lane Limited | Hospitality | 2015 |
| Foley Plumbing Services Ltd | Construction | 2025 |
| Follow ME Ltd | Transport & logistics | 2024 |
| Fonesmart (Rickmansworth) Limited | Information & communication | 2018 |
| Food and Flavours Ltd | Hospitality | 2025 |
| Foray Specialty Ltd | Administrative & support | 2026 |
| Forbes Chapman Ltd | Construction | 2018 |
| Forge Systems Ltd | Information & communication | 2024 |
| Fork and Elbow Ltd | Real estate | 2023 |
| Formlessforms Press Limited | Information & communication | 2022 |
| Formosa, Monro Limited | Other services | 1960 |
| Formula-Fun Ltd | Administrative & support | 2025 |
| Fortify Consulting Ltd | Professional & scientific | 2024 |
| Fortium International Ltd | Professional & scientific | 2025 |
| Fortius Limited | Health & social care | 2025 |
| Fortuna Pictures Ltd | Information & communication | 2023 |
| Forty Lane Developments Ltd | Real estate | 2019 |
| Forwardify Limited | Administrative & support | 2014 |
| FOU Limited | Manufacturing | 2020 |
| Foundry Capital (RE) Ltd | Construction | 2024 |
| FOUNDRY12 Ltd | Administrative & support | 2017 |
| Four One Summit Ltd | Construction | 2026 |
| Foured Media Ltd | Professional & scientific | 2024 |
| Fourways Property Management Ltd | Households | 2007 |