| NO8 Consultancy Services Limited | Professional & scientific | 2025 |
| Northlight Communications Ltd | Professional & scientific | 2025 |
| Novus Teaching Limited | Education | 2007 |
| NP26 Ltd | Construction | 2023 |
| NR Property Living Ltd | Real estate | 2025 |
| Obvious Consult Ltd | Professional & scientific | 2023 |
| OLB Ltd | Arts & recreation | 2023 |
| Omnia Information Technology Ltd | Information & communication | 2024 |
| ON Site 'UV Cure' Flooring Systems Limited | Administrative & support | 2016 |
| One Eighty Refurbishments Ltd | Construction | 2022 |
| One Future Communications Limited | Information & communication | 1999 |
| Oneself Wellbeing Ltd | Manufacturing | 2021 |
| Onespoke Limited | Professional & scientific | 2025 |
| Onsite Engineering Services Ltd | Manufacturing | 2024 |
| ORB Drive Residents Company Limited | Households | 2021 |
| Osceboost Ltd | Education | 2024 |
| Owen Barnes Consulting Ltd | Professional & scientific | 2021 |
| P4D Consulting Limited | Professional & scientific | 2004 |
| Packsafe Group Limited | Other services | 2008 |
| Palman Properties Ltd | Real estate | 2023 |
| Paradiso Home Group Limited | Construction | 2021 |
| Parc Ceirw Garden Village Limited | Households | 2019 |
| PAS Computing Services Ltd | Information & communication | 2003 |
| Paul Leamon Limited | Transport & logistics | 2017 |
| Paws Parlour Limited | Other services | 2022 |
| PCL Lettings Ltd | Real estate | 2022 |
| PD Electrics Ltd | Construction | 2026 |
| Peach Therapies Limited | Health & social care | 2021 |
| Penhow Autograss Car Racing Club Limited | Arts & recreation | 1982 |
| Penylan Country Lodge Holdings Limited | Financial services | 2022 |
| Penylan Country Lodge Kennels & Cattery Limited | Other services | 2022 |
| Penylan Farm Limited | Agriculture & fishing | 2012 |
| Perfect Pet Services Limited | Extraterritorial | 2014 |
| Pettican Welding Services Limited | Construction | 2016 |
| Peytonhannah Ltd | Professional & scientific | 2026 |
| Pezano PVT Ltd | Wholesale & retail | 2025 |
| PG Plant Limited | Administrative & support | 2022 |
| Phoenix Health Care Training Limited | Health & social care | 2019 |
| Phoenix Land Brokers Limited | Real estate | 2011 |
| Pickled Pumpkin Catering Ltd | Hospitality | 2018 |
| Pillo Foods Ltd | Hospitality | 2019 |
| Pinchard Soccer School Limited | Education | 2019 |
| Plane UAV Ltd | Professional & scientific | 2015 |
| Plant and Structural Inspection Services Limited | Professional & scientific | 2006 |
| Platinum CCA Limited | Professional & scientific | 2014 |
| PMS Lettings Ltd | Real estate | 2024 |
| Podium Event Services Ltd | Other services | 2024 |
| Polymer Depolymerisation Limited | Professional & scientific | 2010 |
| Portskewett Accountancy Services Ltd | Professional & scientific | 2013 |
| Posnetics Limited | Information & communication | 1986 |
| PR Consultancy & Management Services Limited | Extraterritorial | 2009 |
| Practical Training Ltd | Education | 2015 |
| Precision Air Contractors Limited | Energy | 2017 |
| Prendergast Travel Limited | Administrative & support | 2019 |
| Prestige CC Ltd | Construction | 2025 |
| Prime Cuts Processing Ltd | Manufacturing | 2025 |
| Prince Plant Repairs Limited | Manufacturing | 2009 |
| Print on ME Ltd | Manufacturing | 2019 |
| Printed and Bound Ltd | Manufacturing | 2025 |
| Professional Associations Research Network | Professional & scientific | 1999 |
| Propconnections Limited | Other services | 2022 |
| Pugh & Mackay Consultancy Limited | Financial services | 2024 |
| Purple Smash Limited | Information & communication | 2011 |
| PW Heating & Plumbing Engineers Limited | Construction | 2013 |
| Qaplus Limited | Information & communication | 1999 |
| Quarter View Properties Limited | Real estate | 2024 |
| R & R Site Services Limited | Manufacturing | 2003 |
| R B M Haulage & Hire Ltd | Transport & logistics | 2013 |
| R L Property and Developments Limited | Construction | 2021 |
| R Thompson Building Services Limited | Construction | 2023 |
| R4 Project Solutions Ltd | Professional & scientific | 2026 |
| Race 500 Limited | Financial services | 2005 |
| Rail Installation & Technical Services Ltd | Manufacturing | 2019 |
| Raintite Trading Limited | Manufacturing | 2006 |
| Random Clicks Limited | Wholesale & retail | 2024 |
| Ratecrest Limited | Professional & scientific | 2016 |
| Rbtv Ltd | Information & communication | 2012 |
| Red Cedar Limited | Real estate | 2004 |
| Red Diamond Homes Ltd | Real estate | 2019 |
| Red Dragon Seeds Ltd | Wholesale & retail | 2023 |
| Red Lantern Newport Ltd | Hospitality | 2022 |
| Redman Development Limited | Information & communication | 2023 |
| Refuel Supply Company Ltd | Wholesale & retail | 2026 |
| Reliance Investments (Caldicot) Ltd | Real estate | 2026 |
| Relklin Limited | Wholesale & retail | 2018 |
| Renwix Limited | Manufacturing | 2013 |
| RES21 Limited | Wholesale & retail | 2021 |
| RES7 Limited | Transport & logistics | 2016 |
| Resinset Ltd | Construction | 2025 |
| Reva Hair Ltd | Other services | 2020 |
| Revolution Performance Mindset Limited | Other services | 2016 |
| REX GDN Limited | Wholesale & retail | 2023 |
| RHB Trading Ltd | Wholesale & retail | 2012 |
| Rhowen Consulting Ltd | Professional & scientific | 2021 |
| Ridinghood Music Ltd | Arts & recreation | 2015 |
| Righthome(Uk) Ltd | Real estate | 2024 |
| Rightway Tech Limited | Wholesale & retail | 2019 |
| Rikifoods Ltd | Wholesale & retail | 2024 |
| Riley CUE Sports Limited | Other services | 1994 |
| Risca Plant Services Ltd | Administrative & support | 2025 |