| Figment Visualisation Limited | Professional & scientific | 2022 |
| Fiitwithmeg Limited | Education | 2025 |
| Filtech 2000 Limited | Water & waste | 1998 |
| Filtek Ltd | Water & waste | 2020 |
| Fima Property Limited | Real estate | 2021 |
| Finance 4 U Group Ltd | Financial services | 2017 |
| Finance Awards Wales Limited | Extraterritorial | 2017 |
| Finance House (Newport) Limited | Administrative & support | 2019 |
| Financial Planning (Wales) Ltd | Administrative & support | 1998 |
| FINBAX1 Limited | Arts & recreation | 2024 |
| Finbogo Limited | Information & communication | 2024 |
| Finchetto Ltd | Professional & scientific | 2020 |
| Find Book Go Limited | Information & communication | 2024 |
| Finncri Resources Limited | Administrative & support | 2024 |
| Finnerty Civils Ltd | Construction | 2017 |
| Finnlilly Trading Limited | Construction | 2015 |
| Finson Interiors Limited | Wholesale & retail | 2022 |
| Fintek Ninjas Limited | Administrative & support | 2021 |
| Firbank 36 Limited | Households | 2021 |
| Fire & Safety Specialists Limited | Wholesale & retail | 2007 |
| Fire Safe Training (IW) Ltd | Administrative & support | 2012 |
| Fire Safety Assured Ltd | Other services | 2022 |
| Firedara Ltd | Wholesale & retail | 2022 |
| Firefighters 66 Ltd | Arts & recreation | 2023 |
| Firefly Analytics Limited | Information & communication | 2016 |
| First AID Wales Ltd | Education | 2009 |
| First Car Fleet Limited | Administrative & support | 2008 |
| First Choice Recruitment Ltd | Administrative & support | 2019 |
| First Choice Roofing Contractors (UK) Ltd. | Construction | 2017 |
| First Choice Tools Ltd | Wholesale & retail | 2020 |
| First Class Gardens and Fencing Ltd | Administrative & support | 2025 |
| First FIX Timber Frames Limited | Manufacturing | 2017 |
| First Light Editions Ltd | Information & communication | 2026 |
| First Principles Care Services Limited | Health & social care | 2022 |
| First Rate Training Limited | Other services | 2013 |
| First Steps Academy Ltd | Health & social care | 2025 |
| FIRST4IT Solutions Limited | Information & communication | 2004 |
| Fiscrop Limited | Agriculture & fishing | 2021 |
| Fishstone Limited | Professional & scientific | 2006 |
| Fit 4 Purpose Property Services Limited | Administrative & support | 2019 |
| Fit Food Prep Limited | Manufacturing | 2016 |
| Fit My Floor Limited | Wholesale & retail | 2016 |
| Fit Prosperity Ltd | Health & social care | 2025 |
| Fitco Ltd | Extraterritorial | 2007 |
| Fitness Factory Oakdale Limited | Arts & recreation | 2023 |
| Fitness Fusion Gym Ltd | Arts & recreation | 2024 |
| Fivew Technology Ltd | Information & communication | 2021 |
| FJ Digitech Ltd | Wholesale & retail | 2025 |
| Fjrepairs Ltd | Manufacturing | 2025 |
| FJT (Wellington) Ltd | Arts & recreation | 2015 |
| FJW Engineering Limited | Construction | 2016 |
| FLA Cleaning Services Limited | Administrative & support | 2024 |
| Flamingo (Ryde) Ltd | Hospitality | 2025 |
| Flamingos Vintage Bristol Limited | Wholesale & retail | 2023 |
| Flamingos Vintage Reading Limited | Wholesale & retail | 2023 |
| Flammez Ltd | Hospitality | 2026 |
| Flams Logistics Ltd | Transport & logistics | 2019 |
| Flarewell Ltd | Professional & scientific | 2013 |
| Flash Freight Ltd | Transport & logistics | 2020 |
| Flash Langdon Ltd | Other services | 2025 |
| Flat Four Auto Werks Ltd | Wholesale & retail | 2026 |
| Flaunt Ltd | Other services | 2021 |
| Flavell's Ltd | Wholesale & retail | 2024 |
| Flavours of the Dragon Ltd | Manufacturing | 2016 |
| Flawless Films Limited | Information & communication | 2016 |
| FLE Property Ltd | Real estate | 2025 |
| Fleet Support Ltd | Wholesale & retail | 2019 |
| Fleurs Forever Ltd | Arts & recreation | 2024 |
| Flexible Commercial Funding Limited | Financial services | 2011 |
| Flexible Finance (Property) Ltd | Real estate | 2025 |
| Flexible Options Limited | Public administration | 2014 |
| Flikclip Limited | Information & communication | 2016 |
| Flinki Limited | Information & communication | 2026 |
| Fllr Properties Limited | Real estate | 2024 |
| Flogard Limited | Professional & scientific | 2010 |
| Flogard Systems Ltd. | Wholesale & retail | 1998 |
| Floor IT IOW Ltd | Construction | 2021 |
| Floorex Carpets Holdings Limited | Financial services | 2025 |
| Flooring Gallery (Newport) Ltd | Construction | 2014 |
| Floradey Limited | Wholesale & retail | 2024 |
| Florcastanha Ltd | Health & social care | 2025 |
| Floreco Dynamics Ltd | Hospitality | 2025 |
| Florian's Services Ltd | Transport & logistics | 2025 |
| Flow Electrical Services (South Wales) Limited | Construction | 2025 |
| Flow Engineering Limited | Construction | 2011 |
| Flowerbelle Barn Ltd | Wholesale & retail | 2018 |
| Flows Technologies Limited | Information & communication | 2026 |
| FLP Properties Ltd | Real estate | 2016 |
| FLS Treecare Ltd | Agriculture & fishing | 2012 |
| Fluidfix Ltd | Wholesale & retail | 2025 |
| Fluyt Design Limited | Professional & scientific | 2025 |
| Flying Bridge Theatre Limited | Arts & recreation | 2016 |
| Flyingtoucan Limited | Information & communication | 2023 |
| Flynns Personalisation & Embroidery Ltd | Wholesale & retail | 2024 |
| FM Empire Ltd | Real estate | 2025 |
| FM Plastering & Building Ltd | Construction | 2022 |
| FM Renovations & Building Ltd | Construction | 2023 |
| FMF Newco Altech Ltd | Extraterritorial | 2014 |
| Foat People Matters Ltd | Administrative & support | 2022 |
| Focal (Rogiet) Ltd | Hospitality | 2018 |