| Osterley Property Investments Limited | Real estate | 2012 |
| Oswi Ltd | Real estate | 2025 |
| Otto Techlabs Limited | Information & communication | 2024 |
| Otto Tours Ltd | Administrative & support | 2024 |
| Oudbliss Ltd | Other services | 2025 |
| OUR Health UK Ltd | Health & social care | 2008 |
| OUR Lady of Christendom Pilgrimage Limited | Other services | 2026 |
| Outlay Ltd | Real estate | 2022 |
| Outpayce UK Limited | Financial services | 2022 |
| Outswork Limited | Wholesale & retail | 2020 |
| Overseas Career Guru Ltd | Information & communication | 2020 |
| Oversoul Ltd | Information & communication | 2023 |
| Ovkarail Ltd | Construction | 2018 |
| Owlsfield Ltd | Administrative & support | 2018 |
| Oxbridge Angels Ltd | Financial services | 2019 |
| Oxbridge Angels Nominees 2020 Ltd | Financial services | 2019 |
| Oxford Care Services Ltd | Education | 2014 |
| Oxford Convenience Store Ltd | Wholesale & retail | 2024 |
| Oxford Quality Construction Ltd | Construction | 2019 |
| OXL Limited | Construction | 2025 |
| Oyinhomes Ltd | Real estate | 2022 |
| Oyli Ltd | Information & communication | 2025 |
| Oystered Limited | Information & communication | 2013 |
| OZ Electrical Limited | Construction | 2019 |
| OZA Trading Limited | Transport & logistics | 2022 |
| P & S Culinary Cosmos Limited | Hospitality | 2023 |
| P & S Foods Limited | Hospitality | 2000 |
| P Lazar Limited | Other services | 2019 |
| P S Builders (UK) Ltd | Construction | 2015 |
| P S Sidhu Properties Limited | Real estate | 2023 |
| P Tobiasz Ltd | Construction | 2017 |
| P&R Enterprise Ltd | Real estate | 2020 |
| P.I.K.S Consulting Limited | Energy | 2025 |
| P.M.K. Property Maintenance Ltd | Construction | 2020 |
| P.W. Secure-It Limited | Construction | 1995 |
| Paan & Sweets Ltd | Wholesale & retail | 2023 |
| Paands Ltd | Wholesale & retail | 2022 |
| Paanivaar Limited | Wholesale & retail | 2025 |
| Paawtopia Limited | Other services | 2025 |
| Pacific Infotech (UK) Ltd | Information & communication | 2008 |
| Packways Limited | Transport & logistics | 2014 |
| Padda and Garcha Construction Limited | Construction | 2025 |
| Padda Autos Limited | Wholesale & retail | 2019 |
| Padda's Nest Limited | Real estate | 2020 |
| Padel Base Ltd | Arts & recreation | 2023 |
| Pagauti Enterprises Limited | Transport & logistics | 2016 |
| Pahuja Traders Ltd | Wholesale & retail | 2026 |
| Paintbrush Limited | Construction | 2015 |
| Painting & Styling Ltd | Construction | 2018 |
| Painting Services Ltd | Construction | 2019 |
| Paisley Corporation Limited | Real estate | 2012 |
| PAK Bizz Ltd | Information & communication | 2025 |
| PAK Halal Poultry (Wholesale) Limited | Wholesale & retail | 2017 |
| Pakbag Ltd | Administrative & support | 2025 |
| Pakistan International ALL Imports and ALL Exports and ALL Cargos Company Ltd | Transport & logistics | 2023 |
| Pakistan International Beauty and Barbers Products Supplies and Imports and Exports and Cargos Company Ltd | Wholesale & retail | 2023 |
| Palace Hair CUT Ltd | Other services | 2021 |
| Palak Trustees Ltd | Financial services | 2026 |
| Palehalo Technologies Ltd | Information & communication | 2026 |
| Paleta Kitchen Ltd | Hospitality | 2015 |
| Palia Builders Ltd | Construction | 2018 |
| Palia Building Ltd | Construction | 2019 |
| Palika Bazar Limited | Wholesale & retail | 2019 |
| Pallet Delivery London Ltd | Transport & logistics | 2024 |
| Pallve London Ltd | Wholesale & retail | 2025 |
| Palmtrix Ltd | Information & communication | 2014 |
| Palushi Transport Ltd | Transport & logistics | 2021 |
| Palwan Builders Ltd | Construction | 2024 |
| Pama Trends Ltd | Wholesale & retail | 2025 |
| Pamir Baguette Limited | Hospitality | 2020 |
| PAN African Network for One Health Consultancy Limited | Public administration | 2024 |
| PAN Euro Foods Limited | Wholesale & retail | 2005 |
| PAN Properties 1 Limited | Wholesale & retail | 2023 |
| Panda Tech Industries Limited | Information & communication | 2024 |
| Pannu Realty Ltd | Real estate | 2025 |
| Panther House Ltd | Information & communication | 2018 |
| Papa's Grill House Ltd | Hospitality | 2014 |
| Papaa Limited | Administrative & support | 2021 |
| Paradise Properties Real Estate UK Ltd | Real estate | 2023 |
| Paradise Salon Ltd | Other services | 2024 |
| Paragon Designs Ltd | Construction | 2022 |
| Paragon Properties London Limited | Real estate | 2025 |
| Paragon Skills Limited | Information & communication | 1990 |
| Paraiso Swim Ltd | Wholesale & retail | 2025 |
| Parallel Metal Limited | Manufacturing | 2025 |
| Parallel Properties Limited | Real estate | 2019 |
| Paramjit Ltd | Construction | 2026 |
| Paramount Construction & Kitchen Ltd | Construction | 2015 |
| Paramount Realty Group Ltd | Real estate | 2025 |
| Parbee Motors Ltd | Wholesale & retail | 2025 |
| Parcel World Limited | Transport & logistics | 2012 |
| Pargat Singh Randhawa Ltd | Construction | 2023 |
| Pari Pizza Takeaway Limited | Hospitality | 2022 |
| Parihar Construction Limited | Construction | 2020 |
| Paris Dillon Holdings Limited | Real estate | 2011 |
| Park at Airport Ltd | Transport & logistics | 2025 |
| Park Lawn Estates Limited | Real estate | 2022 |
| Park Walk Services Ltd | Administrative & support | 2018 |
| Parkhouse Property Group Ltd | Real estate | 2018 |
| Parklands Court Freehold Ltd | Real estate | 2025 |