| Power Athletics- Caerphilly Limited | Arts & recreation | 2015 |
| Power Commercial Savings Limited | Energy | 2009 |
| Ppmcloud Limited | Information & communication | 2012 |
| Precious Brands Ltd. | Professional & scientific | 2012 |
| Premier Financial Services (WM) Ltd | Financial services | 2017 |
| Premier Print (Cardiff) Ltd | Manufacturing | 2012 |
| Premtech Electrical Ltd | Construction | 2011 |
| Premtech Group Holdings Limited | Construction | 2026 |
| Preston A.S. Limited | Extraterritorial | 2012 |
| Preston Accountancy Services Ltd | Professional & scientific | 2002 |
| Preston Investments Limited | Real estate | 2026 |
| Pretty Little Holidays Ltd | Administrative & support | 2024 |
| Price Civil Engineering Limited | Construction | 2025 |
| Price Railway Contractors Ltd | Construction | 2025 |
| Primary Objective Limited | Professional & scientific | 2015 |
| Principal Hygiene Systems Limited | Wholesale & retail | 2001 |
| Print One Promotions Limited | Wholesale & retail | 2012 |
| Print Sauce Associates Limited | Professional & scientific | 2011 |
| Pro Connections Electrical Limited | Construction | 2023 |
| Pro LAY Flooring Ltd | Construction | 2025 |
| Pro-Tect Plumbing & Bathrooms Ltd | Construction | 2026 |
| Process Development Engineering Limited | Manufacturing | 2021 |
| Procter Brothers Ltd | Manufacturing | 2020 |
| Proficient Systems Ltd | Information & communication | 2011 |
| Pronto Hire Limited | Administrative & support | 2015 |
| Propa Support Limited | Administrative & support | 2016 |
| Property Peace of Mind Limited | Real estate | 2010 |
| Protectorcomms Facilities Limited | Information & communication | 2014 |
| Protectorcomms Group Limited | Construction | 2017 |
| Protectorcomms Limited | Construction | 2006 |
| Protool (Wales) Limited | Manufacturing | 2012 |
| Proveit Limited | Information & communication | 2022 |
| Provenance Properties Ltd | Construction | 2023 |
| PSB Financial Advice Limited | Financial services | 2017 |
| Pure Learning Solutions Limited | Professional & scientific | 2024 |
| Purnell Properties Limited | Real estate | 2024 |
| Q30 Limited | Professional & scientific | 2006 |
| QB Recycling Ltd | Water & waste | 2021 |
| QC Grove Park CE Limited | Households | 2015 |
| Qcreativ Ltd | Information & communication | 2026 |
| QL Global CIC | Agriculture & fishing | 2016 |
| Qora AI Limited | Information & communication | 2026 |
| Qtec Facilities Management Ltd | Administrative & support | 2015 |
| Quantum Cost and Construction Management Ltd | Professional & scientific | 2025 |
| Quartz-Lite Limited | Extraterritorial | 2010 |
| Queen B'S Rentals Ltd | Wholesale & retail | 2025 |
| Quickstep Fitness CIC | Arts & recreation | 2023 |
| Quik Clik Ltd | Professional & scientific | 2023 |
| Quote Utilities Ltd | Other services | 2024 |
| R & C Transport Tipper Grab and Skip Hire Limited | Transport & logistics | 2015 |
| R & K Catering Services Limited | Hospitality | 2019 |
| R Movables Ltd | Transport & logistics | 2025 |
| R S Netting Limited | | 2000 |
| R&R Downes Ltd | Real estate | 2020 |
| R19PLM Ltd | Wholesale & retail | 2025 |
| Rack Rent Ltd. | Real estate | 2001 |
| Radecarl Group Limited | Construction | 2024 |
| Radecarl Limited | Real estate | 2005 |
| Radecarl Property Management Ltd | Real estate | 2012 |
| Radford Scaffolding Ltd. | Construction | 2017 |
| Radiance Tanning Studio Ltd | Other services | 2016 |
| RAE Swim Ltd | Manufacturing | 2026 |
| Rage Electrical Wholesale Limited | Wholesale & retail | 2012 |
| Ragsan UK Limited | Wholesale & retail | 2022 |
| Rahere Limited | Real estate | 2021 |
| Raiden Electrical Services Ltd | Construction | 2018 |
| Rainbow Community Travel Services Limited | Transport & logistics | 2009 |
| Rainbow Pooch Pride Ltd | Other services | 2024 |
| RAJ of India Market Street Ltd | Hospitality | 2025 |
| Raldex Ltd | Wholesale & retail | 2022 |
| RAM Plant Ltd | Construction | 2022 |
| Rams & Rams Limited | Wholesale & retail | 2017 |
| Randombird Productions Ltd | Information & communication | 2016 |
| Rangeforce (Frying Ranges) Limited | Manufacturing | 2016 |
| Ranger Three Productions Limited | Information & communication | 2022 |
| Ravens Haven Cleaning Services Ltd | Administrative & support | 2025 |
| RCT Lettings Limited | Real estate | 2024 |
| RE YOU Hair and Beauty Ltd | Other services | 2024 |
| Recrock Ltd | Arts & recreation | 2013 |
| Recruitment FOX Ltd | Administrative & support | 2023 |
| Red DOT Golf Ltd | Professional & scientific | 2019 |
| Red Dragon Caerphilly Ltd | Hospitality | 2026 |
| Red Dragon Inspection Services Limited | Administrative & support | 2017 |
| Red Kite Marine Ltd | Professional & scientific | 2024 |
| Red Raven Consultancy Limited | Information & communication | 2014 |
| Red Raven Group Ltd | Real estate | 2026 |
| Red Rock Equestrian Limited | Agriculture & fishing | 2025 |
| Redbrook Digital Limited | Administrative & support | 2019 |
| Redcastle Classics Limited | Wholesale & retail | 2003 |
| Reddasurv Ltd | Professional & scientific | 2019 |
| Redwood Trees and Landscaping Ltd | Administrative & support | 2024 |
| Reed Group Contracting Ltd | Other services | 2025 |
| Rees & Jackson Logistics Ltd | Transport & logistics | 2023 |
| Render Group SW Ltd | Construction | 2026 |
| Render Life Ltd | Construction | 2018 |
| Renderclean Ltd | Construction | 2021 |
| Renewable Innovations Ltd | Construction | 2012 |
| Renovate South Wales Limited | Construction | 2024 |
| Rent a Fit Online Ltd | Administrative & support | 2024 |
| Rentacrate (UK) Limited | Extraterritorial | 2004 |