| Orris Intelligence Limited | Professional & scientific | 2017 |
| Osaka Sushi Limited | Wholesale & retail | 2024 |
| Osas ET AL Ltd | Professional & scientific | 2022 |
| Oschargo Ltd | Professional & scientific | 2019 |
| Ospheric Creations Limited | Manufacturing | 2024 |
| Osprey Health Consulting Ltd | Professional & scientific | 2016 |
| OSR Pro Sound Ltd | Administrative & support | 2023 |
| Osswind Ltd | Professional & scientific | 2025 |
| Osterbi Limited | Real estate | 2018 |
| Otrc Limited | Health & social care | 2020 |
| OTS Legal Ltd | Professional & scientific | 2014 |
| Otter Jobs Ltd | Administrative & support | 2025 |
| Ourhomeworkclub Ltd | Education | 2017 |
| Outdoor Porcelain Limited | Wholesale & retail | 2025 |
| Outerpress Ltd | Administrative & support | 2025 |
| Ovel Media Ltd | Professional & scientific | 2023 |
| Oventrop UK Limited | Administrative & support | 1992 |
| Overton Bathroom Centre Limited | Construction | 2001 |
| Overton Osteopath Ltd | Health & social care | 2020 |
| Overture Health UK Ltd | Information & communication | 2022 |
| Owen & Kate History Ltd | Education | 2024 |
| Owlicity Ltd | Financial services | 2016 |
| Owlstudio Ltd | Professional & scientific | 2021 |
| Own Your Birth UK Limited | Education | 2023 |
| Owna Ltd | Real estate | 2025 |
| Oxlade Business Solutions Limited | Administrative & support | 2019 |
| Oyin Ltd | Other services | 2023 |
| OZE Energy Ltd | Professional & scientific | 2025 |
| P and GR Grant Consulting Ltd | Professional & scientific | 2009 |
| P F N Finance Limited | Financial services | 2003 |
| P.B. Edwards Construction Limited | Construction | 1991 |
| P.B. Tiba Ltd | Transport & logistics | 2016 |
| P.M.Electrical Systems Limited | Administrative & support | 2008 |
| P.P.A. Interiors Limited | Construction | 2000 |
| P2P Comms Limited | Information & communication | 2022 |
| Pablo Barbers Basingstoke Limited | Other services | 2026 |
| PAC Commercial Ltd | Administrative & support | 2018 |
| Pacific Computers Limited | Information & communication | 1996 |
| Pack Cars Ltd | Wholesale & retail | 2018 |
| Pack Lane Wool Ltd | Wholesale & retail | 2025 |
| Paddle SUP Company Ltd | Education | 2022 |
| Paddysplanet Limited | Professional & scientific | 2022 |
| Padham Properties Limited | Construction | 1949 |
| Paduanelli Holdings Limited | Real estate | 2019 |
| Paff -1 Ltd | Other services | 2018 |
| Pagan Brew Ltd | Wholesale & retail | 2023 |
| Paintball South Ltd | Arts & recreation | 2023 |
| Paiva Ltd | Financial services | 2020 |
| PAL Square Physio Ltd | Public administration | 2020 |
| Palindi Games Limited | Professional & scientific | 2012 |
| Palmer Property Holdings Ltd | Real estate | 2021 |
| Pamela Body Works Ltd | Professional & scientific | 2025 |
| Pampas Audio Limited | Information & communication | 2010 |
| Pampered to Pawfection Ltd | Other services | 2025 |
| PAN Asian Food Corner Ltd | Hospitality | 2023 |
| PAN Asian Spices Ltd | Wholesale & retail | 2025 |
| PAN Books Limited | Extraterritorial | 1944 |
| PAN Bookshops Limited | Extraterritorial | 1955 |
| PAN Macmillan Limited | Extraterritorial | 1982 |
| Panache Dental Care Limited | Health & social care | 2015 |
| Panache Real Estate Limited | Real estate | 2020 |
| Panda Social Care Ltd | Health & social care | 2018 |
| Pang's House Ltd | Real estate | 2016 |
| Pangea Green Limited | Professional & scientific | 2021 |
| Pankhurst Cycles Limited | Manufacturing | 2012 |
| Panto in a Day Ltd | Arts & recreation | 2013 |
| Panwalkar Associates Ltd | Health & social care | 2019 |
| Panza Enterprises Limited | Information & communication | 2010 |
| Paper Makers Ltd | Real estate | 1997 |
| Papillon Luxe Ltd | Other services | 2025 |
| Parabellumldn Limited | Manufacturing | 2023 |
| Paradigm Consulting Asia Limited | Professional & scientific | 2022 |
| Paradise for YOU Ltd | Wholesale & retail | 2020 |
| Paragon Landscapes Ltd | Construction | 2017 |
| Parc Holdings Ltd | Financial services | 2025 |
| Parexel International Corporation Ltd. | Financial services | 2017 |
| Parexel International Holding UK Limited | Professional & scientific | 2008 |
| Parexel International Limited | Professional & scientific | 1988 |
| Parexel MMS Europe Limited | Administrative & support | 1980 |
| Parexel Securitization SPV Limited | Other services | 2018 |
| Pari Estate Ltd | Real estate | 2023 |
| Parkova Systems Limited | Professional & scientific | 2026 |
| Parkside Paving Limited | Construction | 2012 |
| Parkwill Property Limited | Construction | 2022 |
| Parnell Jordy and Harvey Ltd | Real estate | 2015 |
| Parrilla SL Ltd | Construction | 2025 |
| Parties 'N' Play Ltd | Arts & recreation | 2025 |
| Partner Velocity Ltd | Information & communication | 2026 |
| Party Delights Photo Booth Ltd | Administrative & support | 2022 |
| Pass My Theory Test Limited | Education | 2025 |
| Passion Wines Ltd | Wholesale & retail | 2024 |
| Pathway Agency Limited | Professional & scientific | 2017 |
| Patz Holdings Ltd | Professional & scientific | 2025 |
| Paul Barlow Design Ltd | Professional & scientific | 2019 |
| Paul Butler Construction Limited | Construction | 2001 |
| Paul Cresswell Limited | Extraterritorial | 2016 |
| Paul Dalton Ltd | Arts & recreation | 2019 |
| Paul Holdings Limited | Real estate | 2023 |
| Paul Keyte Educational Consultancy Limited | Education | 2024 |
| Paul's Plumbing & Heating Services Ltd | Construction | 2018 |