| FH Worldwide Holdings Limited | Administrative & support | 2023 |
| Fhml Ltd | Information & communication | 2014 |
| Fhnm Group Ltd | Wholesale & retail | 2024 |
| FHS Dynamics Limited | Manufacturing | 1998 |
| Fidelity Care Homes 2 Limited | Real estate | 2023 |
| Fidelity Care Homes Ltd | Health & social care | 2019 |
| Fidelity Healthcare Limited | Health & social care | 2013 |
| Fidelity Healthcare Moormead Limited | Health & social care | 2023 |
| Fidelity Property Investments Limited | Financial services | 2014 |
| Fideran Ltd | Information & communication | 2025 |
| Fidow Limited | Transport & logistics | 2025 |
| Fieldend Properties Ltd | Real estate | 2020 |
| Fieldhurst Motor Company Ltd | Wholesale & retail | 2025 |
| Fifth Key North Limited | Real estate | 2025 |
| Fifth Key Property Ltd | Real estate | 2025 |
| Fifth Rochford (Slough) Management Company Limited | Households | 2025 |
| Fifthdrive Limited | Professional & scientific | 2000 |
| Fifthwheel Haulage Ltd | Transport & logistics | 2025 |
| Fighters Republic CIC | Arts & recreation | 2020 |
| Fiinx Limited | Wholesale & retail | 2014 |
| Fil-Uk Care Ltd | Health & social care | 2013 |
| Fila Transport Ltd | Transport & logistics | 2014 |
| Filemon Maine Coon and Dobermann Cattery Ltd | Agriculture & fishing | 2021 |
| Fill Flow Construction Ltd | Construction | 2021 |
| Fillyrigging Ltd | Construction | 2024 |
| Finalytics Solutions Ltd | Information & communication | 2017 |
| Finance Raiser Ltd | Financial services | 2018 |
| Financial Accountancy Services Ltd | Professional & scientific | 1997 |
| Financial Director Services Limited | Administrative & support | 2024 |
| Finarc Consulting Ltd | Administrative & support | 2017 |
| Fincore Systems Ltd | Wholesale & retail | 2026 |
| Find & FIX Consultants Limited | Transport & logistics | 2013 |
| Find Accessories Limited | Wholesale & retail | 2015 |
| Findernest Limited | Information & communication | 2024 |
| Finding Words Ltd | Health & social care | 2019 |
| Findit SMART99 Ltd | Wholesale & retail | 2025 |
| Fine Contractors Ltd | Construction | 2020 |
| Fine Deco Carpets Ltd | Wholesale & retail | 2019 |
| Fine Deco Group Limited | Construction | 2023 |
| Fine Deco Ltd | Other services | 2018 |
| Fine Deco Tiles Limited | Other services | 2022 |
| Fine Gold Ltd | Manufacturing | 2025 |
| Fine Wine Slough Ltd | Wholesale & retail | 2022 |
| Fine-Tuners Ltd | Wholesale & retail | 2024 |
| Finesse Furniture Limited | Wholesale & retail | 1978 |
| Finesse Kitchens & Bathrooms Ltd | Construction | 2019 |
| Finestcartuk Ltd | Wholesale & retail | 2026 |
| Finetech Solutions Ltd | Wholesale & retail | 2025 |
| Finethyca (UK) Ltd | Professional & scientific | 2024 |
| Finetouch Contractors Ltd | Construction | 2024 |
| Finhive Consultants Ltd | Professional & scientific | 2023 |
| Fininvest (Chaplin Court) Ltd | Real estate | 2024 |
| Finnigan Rail Ltd | Professional & scientific | 2021 |
| Finnovate Limited | Professional & scientific | 2008 |
| Finnrow IT Consulting Ltd | Information & communication | 2026 |
| Finphils Afro Meals Limited | Wholesale & retail | 2026 |
| Fintechsavvy Ltd. | Information & communication | 2025 |
| Fintraconsulting Ltd | Information & communication | 2023 |
| Fiona Beauty & Spa Ltd | Other services | 2019 |
| Fiona Hewin Psychology Ltd | Health & social care | 2024 |
| Fiona Wheeler Limited | Professional & scientific | 2011 |
| Firas Private Limited | Manufacturing | 2026 |
| Firdous Mohyuddin Ltd | Health & social care | 2023 |
| Fire & Security Compliance Services Ltd | Professional & scientific | 2022 |
| Fire Element Engineers UK Limited | Professional & scientific | 2026 |
| Fire Proof Investment Ltd | Public administration | 2019 |
| Fire Safety 4YOU Ltd | Construction | 2019 |
| Fire Spark Safety Ltd | Administrative & support | 2019 |
| Fire Sprinkler Design Consultancy Ltd | Other services | 2013 |
| Firefly Markers Limited | Wholesale & retail | 2013 |
| Firn Products Ltd | Wholesale & retail | 2023 |
| First Accountancy Services Limited | Professional & scientific | 2008 |
| First Airport Transfers Ltd | Transport & logistics | 2026 |
| First Alliance Global Ltd | Wholesale & retail | 2025 |
| First Call Site Services Ltd | Administrative & support | 2022 |
| First Capital (UK) Limited | Real estate | 2012 |
| First Choice Locksmiths Ltd | Administrative & support | 2025 |
| First Class Auto Dealership Ltd | Wholesale & retail | 2014 |
| First Class Cleaning Services Ltd | Administrative & support | 2018 |
| First Contact Cleaning Services Limited | Administrative & support | 2026 |
| First Dog Films Limited | Information & communication | 2025 |
| First Eagle Security Services Limited | Administrative & support | 2022 |
| First Energy (UK) Limited | Financial services | 2011 |
| First Estates (UK) Limited | Real estate | 2011 |
| First European Credit Limited | Administrative & support | 1990 |
| First Green Hire Limited | Other services | 2015 |
| First Impressions Consultants Limited | Education | 2019 |
| First Klass Marquees Limited | Administrative & support | 2019 |
| First Step Merchants Ltd | Wholesale & retail | 2020 |
| First Steps Catering Limited | Hospitality | 2023 |
| Firstautomation Ltd | Professional & scientific | 2024 |
| Firstbio Limited | Hospitality | 2023 |
| Fiscal Fusion Limited | Professional & scientific | 2024 |
| Fishveg Ltd | Agriculture & fishing | 2022 |
| Fisik Pharma Ltd | Wholesale & retail | 2022 |
| Fit 2 Fight MMA UK Limited | Arts & recreation | 2021 |
| Fit Fusion Health and Coaching Ltd | Education | 2024 |
| Fit Gains Limited | Other services | 2023 |
| Fit Pact Limited | Wholesale & retail | 2017 |
| Fit&Move Services Ltd | Transport & logistics | 2024 |