| FL Club Limited | Hospitality | 2025 |
| FLA Security Ltd | Construction | 2015 |
| Flag Hunter Ltd | Arts & recreation | 2025 |
| Flame Kebab House Ltd | Hospitality | 2022 |
| Flamenco Consulting Limited | Professional & scientific | 2024 |
| Flaminco Pizza Ltd | Hospitality | 2023 |
| Flaming Hot Heating Ltd | Construction | 2022 |
| Flange Integrity Limited | Manufacturing | 2018 |
| Flat Pack Swansea Ltd | Administrative & support | 2017 |
| Flavia Integrated Services Ltd | Construction | 2026 |
| Flavour UN Limited | Extraterritorial | 2014 |
| Flavours of Spice Limited | Hospitality | 2017 |
| Flawless Cleaning & Maintenance Services (Wales) Limited | Administrative & support | 2023 |
| Flawless Detailing Ltd. | Wholesale & retail | 2016 |
| FLD Electrical Ltd. | Construction | 2019 |
| Fleet Properties Limited | Financial services | 1964 |
| Fleet Vans Direct Ltd | Wholesale & retail | 2021 |
| Fleetwise Consultancy & Training Ltd | Professional & scientific | 2026 |
| Fletcher Clement Ltd | Information & communication | 2017 |
| Flex Electrical Installations Limited | Construction | 2024 |
| Flexi-Med International (FMI) Limited | Manufacturing | 2020 |
| Flexible Vehicle Solutions Limited | Wholesale & retail | 2021 |
| Flights UN Limited | Extraterritorial | 2013 |
| Flip Side Coffee Ltd | Hospitality | 2026 |
| Flipthink Limited | Professional & scientific | 2022 |
| Flixfoto Ltd | Professional & scientific | 2020 |
| FLO and Sons Transport Ltd | Transport & logistics | 2018 |
| FLO Care UK Ltd | Health & social care | 2024 |
| Flood Consult International Limited | Professional & scientific | 2017 |
| Flooring & Beyond Ltd | Construction | 2025 |
| FLOORS2HOMES Ltd | Wholesale & retail | 2020 |
| Flora Homes Ltd | Real estate | 2026 |
| Florence and Fox's Kitchen Ltd | Hospitality | 2022 |
| Florence LEE Estates Ltd | Real estate | 2025 |
| Florence Opportunities (Carmarthen) Ltd | Other services | 2013 |
| Florence Opportunities Ltd | Other services | 2009 |
| Florique Ltd | Wholesale & retail | 2026 |
| Flos Properties Ltd | Real estate | 2025 |
| Flow Chocolate Ltd | Manufacturing | 2019 |
| Flow-Lec Ltd | Construction | 2003 |
| Flowlong Limited | Real estate | 1996 |
| Fluid Boat Services Limited | Manufacturing | 2015 |
| Flush H2O Ltd | Construction | 2022 |
| Fluxpay Limited | Financial services | 2025 |
| Flying Centre (Wales) Limited | Other services | 2012 |
| Flynn Family Limited | Financial services | 2025 |
| Flynn's Coffee Limited | Wholesale & retail | 2025 |
| Flynns Deli Limited | Wholesale & retail | 2025 |
| FM Contracting Solutions Ltd | Construction | 2017 |
| FM Transport Swansea Limited | Transport & logistics | 2023 |
| FMC (Swansea) Limited | Administrative & support | 2016 |
| FMD Property Services Ltd | Construction | 2025 |
| Fmdc Services Ltd | Professional & scientific | 2018 |
| FN Vaughan Developments Limited | Real estate | 2019 |
| FNP Finance Ltd | Financial services | 2015 |
| Foam Coffi Limited | Hospitality | 2025 |
| Fobou Limited | Wholesale & retail | 2023 |
| Focused Care Services Ltd | Health & social care | 2025 |
| Focused on Care (South Wales) Limited | Health & social care | 2025 |
| Focused on Care Ltd | Health & social care | 2025 |
| Focused Property Group Ltd | Real estate | 2026 |
| Focust Solutions Ltd | Information & communication | 2022 |
| Folk Films Ltd | Information & communication | 2016 |
| Folland Court (1989) Management Limited | Households | 1989 |
| Folly Farm Holiday Park Limited | Professional & scientific | 2019 |
| Folly Farm Holidays Limited | Professional & scientific | 2019 |
| Folly Farm Limited | Professional & scientific | 2004 |
| Fone Wizard Ltd | Wholesale & retail | 2019 |
| Food by Sean Deli & Kitchen Ltd | Hospitality | 2021 |
| Food by Sean Limited | Hospitality | 2020 |
| Food NET House Limited | Hospitality | 2015 |
| Food Safety Technical Support Limited | Hospitality | 2024 |
| Food UN Limited | Extraterritorial | 2013 |
| Food Zone Ltd | Hospitality | 2020 |
| Foodi World Ltd | Wholesale & retail | 2019 |
| Foodisy Limited | Other services | 2017 |
| Footpathproperties Ltd | Construction | 2025 |
| Footy Frogs Ltd | Arts & recreation | 2018 |
| FOR the Girls Ltd | Professional & scientific | 2025 |
| Fordpad Limited | Water & waste | 1982 |
| Fords Social and Sports Club Limited | Hospitality | 2005 |
| Forest Flower (Gowerton) Ltd | Hospitality | 2013 |
| Forest Housing Ltd | Real estate | 2025 |
| Forest Renewable Energy Ltd | Professional & scientific | 2025 |
| Forest View Storage Ltd | Administrative & support | 2017 |
| Forever Grace W&Y Ltd | Hospitality | 2026 |
| Forever Hill Ltd | Professional & scientific | 2024 |
| Forever KIN Healthcare Ltd | Health & social care | 2023 |
| Forever Mortal Ltd | Information & communication | 2020 |
| Forever Trevor Limited | Information & communication | 2014 |
| Forge Surf Ltd | Wholesale & retail | 2024 |
| Forget ME NOT Dementia Day Clubs Ltd | Health & social care | 2015 |
| Fork FIX Hire UK Ltd | Administrative & support | 2021 |
| Formatt Hitech Ltd. | Manufacturing | 2004 |
| Forms Construction Ltd | Construction | 2013 |
| Formwise Export Limited | Information & communication | 1992 |
| Fortis Veritas Limited | Professional & scientific | 2025 |
| Fortress Capital Advisors Limited | Financial services | 2018 |
| Fortuitous Capital Ltd | Financial services | 2018 |
| Forward Holdings Wales Limited | Construction | 2000 |