| NTL Roofing Ltd | Construction | 2026 |
| Number 57 Ltd | Construction | 2025 |
| NXP Advisory Ltd | Transport & logistics | 2021 |
| NÜ Wellness Club Ltd | Health & social care | 2025 |
| O Malyn Ltd | Construction | 2026 |
| O&F Safety & Compliance Ltd | Professional & scientific | 2025 |
| O.P.Welding Ltd | Construction | 2022 |
| O.W.P Land & Property Ltd | Real estate | 2014 |
| Occaction Ltd | Education | 2022 |
| Ocean View Holdings Ltd | Financial services | 2022 |
| Ohmega Consultancy Ltd | Professional & scientific | 2025 |
| Ohmega Power Ltd | Professional & scientific | 2025 |
| Ojph Property Ltd | Real estate | 2021 |
| Old Oaktree Management Limited | Households | 2020 |
| Oligas Ltd | Construction | 2016 |
| Olivander Group Ltd | Administrative & support | 2016 |
| Olive & Bloom Ltd | Wholesale & retail | 2025 |
| Olive Tree Construction Neath Ltd | Construction | 2025 |
| ON Dream Street Ltd | Arts & recreation | 2025 |
| ONA Beauty Studio Ltd | Other services | 2025 |
| Once Upon a Time Childcare Limited | Health & social care | 2019 |
| One Step Counselling and Therapies C.I.C. | Health & social care | 2023 |
| Oneev Limited | Information & communication | 2024 |
| Opco Consulting Ltd | Professional & scientific | 2025 |
| Open Kitchen 2022 Limited | Hospitality | 2022 |
| Optimum Financial Group Limited | Financial services | 2014 |
| Organisedfun.Com Ltd | Arts & recreation | 2018 |
| Oriel Technical Services Ltd | Construction | 2013 |
| ORM Commercial Properties Ltd | Real estate | 2026 |
| ORM Domestic Properties Ltd | Real estate | 2026 |
| Oseafood Ltd | Hospitality | 2022 |
| OUT on the Tiles Ltd | Construction | 2013 |
| Over the Moon Board Services Ltd | Administrative & support | 2023 |
| P & a Grey Limited | Administrative & support | 2012 |
| P & M Electrical Limited | Construction | 2015 |
| P Evans Consultancy Limited | Professional & scientific | 2011 |
| P Hopkins Properties Ltd | Professional & scientific | 2022 |
| P Jones Electrical Ltd | Construction | 2025 |
| P R Wassell Trading Limited | Agriculture & fishing | 2026 |
| P W Harper Limited | Construction | 2024 |
| P&R Properties and Maintenance Ltd | Construction | 2024 |
| P. Elkins Construction Limited | Construction | 2006 |
| P. W. S. (South Wales) Limited | Administrative & support | 2006 |
| Pa-Pa Designs Ltd | Administrative & support | 2014 |
| Pacs Commerce Ltd | Wholesale & retail | 2024 |
| Pacs Electrical Solutions Ltd | Construction | 2021 |
| PADEL4PAWB Ltd | Arts & recreation | 2026 |
| Palexra Ltd | Information & communication | 2017 |
| Pals Childcare Limited | Health & social care | 2025 |
| Pantyffordd Community Hall | Arts & recreation | 2011 |
| Papserv Enterprises Ltd | Professional & scientific | 2020 |
| Paragon Engineered Timber Limited | Manufacturing | 2018 |
| Park & Ride Cycling Hub Community Interest Company | Agriculture & fishing | 2025 |
| Parker Fraser Limited | Health & social care | 2018 |
| Parker Property Rentals Ltd | Real estate | 2024 |
| Parkside Professional Services Ltd | Construction | 2022 |
| Partslink Direct Ltd | Wholesale & retail | 2025 |
| Party at Peets Limited | Information & communication | 2013 |
| Paul Cranny Travel Limited | Administrative & support | 2017 |
| Paul James Building Contractor Ltd | Construction | 2015 |
| Paul Lewis Ltd | Professional & scientific | 2014 |
| Pawsh Paws Ltd | Other services | 2025 |
| Pawsome Group Ltd | Other services | 2024 |
| Pay-Cycle Limited | Administrative & support | 2017 |
| PBS Developments Ltd | Real estate | 2026 |
| PBS Telecom Limited | Information & communication | 2011 |
| PCR Global Limited | Professional & scientific | 2019 |
| Peacock Property Sourcing Ltd | Real estate | 2020 |
| Pembrokeshire Boat Tours Ltd | Administrative & support | 2025 |
| PEN Isar Coed Farm Limited | Agriculture & fishing | 2003 |
| Penderyn Sawmills Ltd | Manufacturing | 2025 |
| Penfold Property and Consultancy Ltd | Real estate | 2025 |
| Pennyford Holdings Ltd | Professional & scientific | 2019 |
| Penscynor Court Limited | Professional & scientific | 2006 |
| Perfect Gardens Bristol Limited | Administrative & support | 2025 |
| Pergwm Holdings Limited | Financial services | 2022 |
| Personalized Gift by Candice Ltd | Wholesale & retail | 2025 |
| Pesw Ltd | Construction | 2023 |
| Peter Green GAS Services Limited | Construction | 2017 |
| Peter James Pharmacy Limited | Wholesale & retail | 2011 |
| Petroleums Gartref Ltd | Professional & scientific | 2006 |
| Petty Properties Limited | Real estate | 2025 |
| Phase 3 Property Ltd | Real estate | 2024 |
| PHC Group Limited | Construction | 2006 |
| Phillips & SON Roofing Ltd | Construction | 2022 |
| Physical Empowerment CIC | Other services | 2021 |
| Physical Therapy & Rehab Ltd | Other services | 2024 |
| Physora Limited | Health & social care | 2025 |
| Pictures UP 321 Ltd | Information & communication | 2015 |
| Pinnacle Scaffolding Ltd | Administrative & support | 2015 |
| Pintech Software Limited | Information & communication | 2021 |
| Pizza Hub Neath Ltd | Hospitality | 2025 |
| Pizza Hub Swansea Ltd | Hospitality | 2025 |
| Pizza Master Ltd | Hospitality | 2025 |
| Pizza Napoli Neath Ltd | Hospitality | 2025 |
| PJ Blackwood Ltd | Administrative & support | 2016 |
| PJ Painting Coatings Ltd | Manufacturing | 2024 |
| Place & Space CIC | Professional & scientific | 2026 |
| Place Dyer Products Limited | Wholesale & retail | 2022 |
| Plane Colours Limited | Construction | 2003 |