| Plantain Kitchen Limited | Hospitality | 2019 |
| Plantask Limited | Information & communication | 2002 |
| Plantblue Recruits Ltd | Administrative & support | 2022 |
| Plantem Capital Limited | Construction | 2022 |
| Plas Bwlch | Financial services | 2021 |
| Plas Dorlan (Cowbridge) Management Company Limited | Households | 2020 |
| Plas Pilates Limited | Arts & recreation | 2020 |
| Plas Y Coed Developments UK Limited | Construction | 2012 |
| Plasdŵr Management Company Limited | Real estate | 2016 |
| Plasnewydd Property Limited | Hospitality | 2000 |
| Plassey Fish Bar Limited | Hospitality | 2014 |
| Plastall Limited | Manufacturing | 1999 |
| Plastic Free Shaving Co Limited | Wholesale & retail | 2021 |
| Plastic Insulated Cables Limited | Manufacturing | 1956 |
| Plastic Recovery Solutions Limited | Extraterritorial | 2019 |
| Plastico Group Ltd. | Water & waste | 2008 |
| Platelink UKI Ltd | Information & communication | 2024 |
| Platform System Ltd | Professional & scientific | 2018 |
| Platinum Agency Group Ltd | Real estate | 2022 |
| Platinum Bay (Trading) Limited | Wholesale & retail | 2012 |
| Platinum Chef Services Limited | Hospitality | 2018 |
| Platinum Cleaning Go Ltd | Administrative & support | 2025 |
| Platinum Computer Sales Ltd | Wholesale & retail | 2024 |
| Platinum Contractors Ltd | Construction | 2018 |
| Platinum Cuts Ltd | Other services | 2026 |
| Platinum Engineering Services Ltd | Manufacturing | 2022 |
| Platinum Financial Consultancy Ltd | Financial services | 2020 |
| Platinum Group Properties Limited | Hospitality | 2016 |
| Platinum Leasing Ltd | Wholesale & retail | 2017 |
| Platinum Legal Services LLP | | 2025 |
| Platinum Luxury Limited | Other services | 2016 |
| Platinum Mechanical & Plumbing Services Limited | Construction | 2019 |
| Platinum One Consulting Limited | Professional & scientific | 2021 |
| Platinum Optical Ltd | Professional & scientific | 2011 |
| Platinum Paradigm Ltd | Administrative & support | 2016 |
| Platinum Programme Ltd | Other services | 2018 |
| Platinum Property Development Cardiff Ltd | Construction | 2024 |
| Platinum Rentals LLP | | 2024 |
| Platinum Ring Company Limited | Wholesale & retail | 2004 |
| Platinum Security Solutions Ltd | Administrative & support | 2018 |
| Platinum Shield Global Services Ltd | Professional & scientific | 2025 |
| Platinum Shields Security Management Limited | Administrative & support | 2019 |
| Platinum Traders International Ltd | Wholesale & retail | 2025 |
| Platinum Vehicle Services Cardiff Ltd | Manufacturing | 2017 |
| Platinumgate Properties Ltd | Real estate | 2026 |
| Platnum Apparel Limited | Wholesale & retail | 2024 |
| Plato Tech Ltd | Information & communication | 2025 |
| Plax Jewellery UK Limited | Wholesale & retail | 2017 |
| Play Bella Limited | Wholesale & retail | 2013 |
| Play Legends Ltd | Information & communication | 2020 |
| Playback Arts Limited | Arts & recreation | 2005 |
| Playbook Consultancy Ltd | Education | 2019 |
| Playdays Parties Limited | Arts & recreation | 2017 |
| Player Assist Ltd | Professional & scientific | 2020 |
| Players Sportswear Ltd. | Other services | 2019 |
| Players Watches Limited | Wholesale & retail | 2018 |
| Playgroundworks Limited | Other services | 2018 |
| Playsocial Ltd | Professional & scientific | 2025 |
| Playthru Limited | Information & communication | 2021 |
| Playtimextra C.I.C. | Education | 2015 |
| Playworks Childcare Limited | Education | 2004 |
| Playworks Early Days Nursery Bedwas Limited | Education | 2006 |
| Playworks Playsports Limited | Education | 2014 |
| PLD Engineering Ltd | Manufacturing | 2025 |
| PLE Concepts Limited | Professional & scientific | 2016 |
| Pleasant Recruiters Ltd | Administrative & support | 2018 |
| Pledge Finds Ltd | Wholesale & retail | 2025 |
| Pleiades Performance Ltd | Wholesale & retail | 2025 |
| Plenico Ltd | Wholesale & retail | 2025 |
| Plentyn Ltd | Wholesale & retail | 2025 |
| Pleroma Academy Limited | Public administration | 2019 |
| Plettac NSG PLC | Wholesale & retail | 1978 |
| Plexpad Ltd | Real estate | 2022 |
| PLF Holdings Limited | Financial services | 2018 |
| PLF International Limited | Manufacturing | 2001 |
| PLF Trading Company Limited | Professional & scientific | 2024 |
| PLF Wealth Management Limited | Financial services | 2001 |
| PLG Estates Limited | Real estate | 2024 |
| PLM Fencing Ltd | Construction | 2017 |
| PLM Plumbing & Heating Ltd. | Construction | 2020 |
| Ploceia Limited | Wholesale & retail | 2025 |
| Plomo Worx Ltd | Construction | 2020 |
| Plotwise Limited | Real estate | 2025 |
| Ploutos Group Limited | Transport & logistics | 2017 |
| PLR Psychology Ltd | Education | 2025 |
| Plsvfx Limited | Information & communication | 2024 |
| Pluckley Station Road Ltd | Real estate | 2022 |
| Pluen WEN Limited | Professional & scientific | 2022 |
| Plug (EV Stations) Limited | Construction | 2022 |
| Plug Doctors Ltd | Wholesale & retail | 2025 |
| Pluggedin Holdings Limited | Information & communication | 2025 |
| Plugxify Ltd | Information & communication | 2025 |
| Plumber Team London Ltd | Construction | 2019 |
| Plumbfixer Ltd | Construction | 2023 |
| Plumbget Ltd | Wholesale & retail | 2021 |
| Plumbing and Heating by Claire Ltd | Construction | 2024 |
| Plumbing and Porcelain Limited | Wholesale & retail | 2025 |
| Plumbing Solutions U.K Limited | Construction | 2018 |
| Plumbline Cardiff Ltd | Construction | 2016 |
| Plumbquik Ltd | Construction | 2020 |