| Outside-In Engineering Ltd | Professional & scientific | 2021 |
| Overseas Travel of UK Ltd | Administrative & support | 2026 |
| Overstone Associates Limited | Professional & scientific | 2012 |
| Ownminder Limited | Information & communication | 2019 |
| OX TAB Limited | Wholesale & retail | 2022 |
| Oxford Medistress Ltd | Professional & scientific | 2005 |
| Oxford Risk Management Ltd | Extraterritorial | 2016 |
| Oxford Talent Group Ltd | Information & communication | 2020 |
| Oxna Investments LLP | | 2021 |
| Oxna Limited | Professional & scientific | 2008 |
| Oxque Farms Limited | Agriculture & fishing | 2016 |
| Oxygana Ltd | Real estate | 2018 |
| P D 2017 Limited | Professional & scientific | 2017 |
| P J Chambers Consulting Limited | Administrative & support | 2008 |
| P W Nichols Ltd | Professional & scientific | 2020 |
| P. Kirby Racing Ltd | Extraterritorial | 2019 |
| P1 Communications Limited | Professional & scientific | 2005 |
| P1 Recruitment Limited | Professional & scientific | 2016 |
| Packpeer Limited | Wholesale & retail | 2024 |
| Padelhud Ltd | Manufacturing | 2025 |
| Padl Property Limited | Real estate | 2020 |
| PAE Professional Services LLC | | 2018 |
| Pagoda Education Limited | Financial services | 2023 |
| Pagoda Energy Services Ltd | Professional & scientific | 2016 |
| Pagoda Words Limited | Information & communication | 2007 |
| PAJ Associates Limited | Administrative & support | 2023 |
| Pajs Services Ltd | Professional & scientific | 2020 |
| Pajubr Ltd | Wholesale & retail | 2022 |
| Palanki C K Services Limited | Transport & logistics | 2025 |
| Palas Technologies Ltd | Information & communication | 2024 |
| Pallett Hill Sand & Gravel Co. Limited | Mining & quarrying | 1960 |
| Palm Partners | Financial services | 2018 |
| Palm Pilates Ltd | Arts & recreation | 2024 |
| Paloma Studio Ltd | Wholesale & retail | 2024 |
| Panache Travel Group Limited | Administrative & support | 2020 |
| Panda Motor Solutions Ltd | Administrative & support | 2026 |
| Pandora's Productions Limited | Other services | 2023 |
| Panlogic Limited | Information & communication | 1999 |
| Panlogic Partners LLP | | 2025 |
| Panorama Hospitality Ltd | Professional & scientific | 2015 |
| Panorama Limited | Real estate | 1991 |
| Pans Hill Advisors Ltd | Wholesale & retail | 2024 |
| Parabola Works Ltd | Wholesale & retail | 2020 |
| Paragon Consultants Limited | Professional & scientific | 2002 |
| Paragon Home Healthcare Ltd | Health & social care | 2018 |
| Paragordo Limited | Professional & scientific | 2020 |
| Parallax Cinematics Ltd | Information & communication | 2023 |
| Paratus Paymasters Limited | Professional & scientific | 2023 |
| Paremata Resources Ltd | Professional & scientific | 2016 |
| Parfum LE Dance Ltd | Manufacturing | 2024 |
| Parisalon Beauty Limited | Other services | 2021 |
| Park Avenue Capital UK Ltd | Administrative & support | 2025 |
| Park Close (Richmond) Residents Association Limited | Households | 1969 |
| Park Corporate Finance Limited | Professional & scientific | 2020 |
| Park Green (Salcombe) Limited | Real estate | 2018 |
| Park Green (South West) Limited | Construction | 2011 |
| Park Green Holdings Limited | Real estate | 2004 |
| Park Green Property Limited | Construction | 2016 |
| Park Green Real Estate Limited | Real estate | 2004 |
| Parker Clinical Ltd | Health & social care | 2025 |
| Parker Prestige Limited | Wholesale & retail | 2016 |
| Parkinson Machinery Ltd | Wholesale & retail | 2021 |
| Parklane Property Portfolio Limited | Real estate | 2020 |
| Parkrun Global Limited | Arts & recreation | 2015 |
| Parkrun Limited | Arts & recreation | 2010 |
| Parkrun Trading Limited | Arts & recreation | 2007 |
| Parkshill Investments Ltd | Real estate | 2025 |
| Parkshot Audit LLP | | 2008 |
| Parkside Builders (KEW) Limited | | 1986 |
| Parkwood Associates Ltd | Professional & scientific | 2021 |
| Parrsouth Limited | Real estate | 1998 |
| Parthian Medical Services Limited | Health & social care | 2024 |
| Partition Dismantling Services Limited | Construction | 2004 |
| Partnership Care & Support Ltd | Health & social care | 2021 |
| Partum.Ai Ltd | Information & communication | 2026 |
| Party 4 Tots Ltd | Arts & recreation | 2004 |
| Partylol London Limited | Real estate | 2019 |
| Patentica Limited | Professional & scientific | 2016 |
| Patrick Courtney Limited | Professional & scientific | 2005 |
| Paul J Hayes Limited | Construction | 2005 |
| Paul Lyons Automotive Limited | Wholesale & retail | 2009 |
| Paul Rodriguez Music Limited | Information & communication | 1983 |
| Pauline Paul (UK) Limited | Other services | 1993 |
| Pavaro Ltd | Real estate | 2024 |
| Paved Court Limited | Hospitality | 2023 |
| PAW Mark Prints Ltd | Arts & recreation | 2020 |
| PAX Bellum Consulting Ltd | Professional & scientific | 2021 |
| Paxton Property Portfolio Ltd | Real estate | 2023 |
| Payco Solutions Ltd | Transport & logistics | 2020 |
| Payfox Limited | Construction | 2022 |
| PB Property Ltd | Real estate | 2022 |
| Pbpm Limited | Professional & scientific | 2024 |
| PD Roofing Solutions Ltd | Construction | 2025 |
| PDM OFF Road Limited | Wholesale & retail | 2023 |
| Peace of Work Limited | Information & communication | 2023 |
| Peacock Property Rentals Limited | Real estate | 2024 |
| Peacocks Wholesale Provisions Ltd | Wholesale & retail | 2016 |
| Pealing Associates Ltd. | Professional & scientific | 2011 |
| Pear Tree Honey Farm Limited | Manufacturing | 2006 |
| Pearl Button Ltd | Professional & scientific | 2019 |