| Oxalide Limited | Wholesale & retail | 2013 |
| Oxford and Cambridge Education Group (UK) Ltd | Real estate | 2014 |
| Oxford Chambers (NG1) Management Co Ltd | Real estate | 2010 |
| Oxford English Academy Ltd | Education | 2023 |
| Oxford House (Ruddington) Ltd | Real estate | 2023 |
| Oxford Spires (Oxford) Limited | Financial services | 2014 |
| Oxford Spires LLP | | 2015 |
| Oxfordshire Nurseries Limited | Health & social care | 2004 |
| Oxley's Installations Limited | Construction | 2024 |
| Oxspring Ltd | Transport & logistics | 2022 |
| Oxton Communications Ltd | Other services | 2025 |
| Oxygen Hair and Beauty Limited | Other services | 2017 |
| Oxygen Solutions Limited | Real estate | 2019 |
| Oyster FRC Ltd | Construction | 2026 |
| Oyster Packaging Group Limited | Administrative & support | 2019 |
| Oyster Retail Packaging Ltd | Administrative & support | 2006 |
| OZ Bar Delivery Ltd | Real estate | 2020 |
| OZ Electrical Services Ltd | Construction | 2025 |
| OZ Pharmaceutical Limited | Wholesale & retail | 2025 |
| OZ Stonebay Ventures Ltd | Wholesale & retail | 2025 |
| Ozai Enterprises Ltd | Wholesale & retail | 2021 |
| Ozan Barbers INT Limited | Other services | 2026 |
| Ozbas Ltd | Construction | 2020 |
| Ozeki Operations Limited | Professional & scientific | 2018 |
| Ozzy Tobias Media Ltd | Information & communication | 2023 |
| O’Connor Reinforcement Limited | Construction | 2019 |
| O’Connors Bridgford Limited | Hospitality | 2024 |
| P & C Properties (ILK) Limited | Real estate | 2019 |
| P & C Property Rental Company Limited | Real estate | 2015 |
| P & D Stores Limited | Wholesale & retail | 2025 |
| P & E Kelly Consulting Ltd | Administrative & support | 2020 |
| P & H Cuisines Limited | Manufacturing | 2019 |
| P & H Property Services Limited | Extraterritorial | 2009 |
| P & J Witney Limited | Professional & scientific | 2016 |
| P & J'S Confectionaries Ltd | Hospitality | 2025 |
| P & K Services Limited | Construction | 2021 |
| P & P Clarke Limited | Real estate | 2017 |
| P & R Transport Ltd | Transport & logistics | 2020 |
| P & S Healthcare Limited | Manufacturing | 2004 |
| P & S Sales and Service Limited | Wholesale & retail | 2026 |
| P & W Builders Ltd | Administrative & support | 2010 |
| P a Cobb Limited | Financial services | 2008 |
| P a Hooley Limited | Construction | 2007 |
| P and R Fabrics (Hucknall) Limited | Manufacturing | 2000 |
| P Armstrong Interiors Ltd | Construction | 2017 |
| P B Future Solutions Ltd | Information & communication | 2021 |
| P Clark Ltd | Construction | 2026 |
| P D Harrison Developments Limited | Construction | 2015 |
| P D K (UK) Limited | Administrative & support | 2003 |
| P D Mulvihill Consulting Limited | Professional & scientific | 2015 |
| P D Thurley Healthcare Ltd | Health & social care | 2026 |
| P G Health Limited | Health & social care | 2022 |
| P G Keane Properties Ltd | Real estate | 2018 |
| P J Hamson & Co. Limited | Professional & scientific | 2005 |
| P J Lilley (Holdings) Limited | Construction | 2005 |
| P J Lilley Ltd. | Construction | 1999 |
| P J T Electrical Services Limited | Construction | 2006 |
| P J T Plant Limited | Administrative & support | 2006 |
| P J Towey Construction Limited | Administrative & support | 2006 |
| P J Towey Holdings Limited | Financial services | 2013 |
| P K Consulting & Accounting Services Limited | Extraterritorial | 2001 |
| P K Daffu Ltd | Public administration | 2022 |
| P K Patel Limited | Health & social care | 2008 |
| P L R Retails Limited | Wholesale & retail | 2025 |
| P M and L J Lyon LLP | | 2019 |
| P M Dodds Consultant Limited | Professional & scientific | 2019 |
| P M Sports Cars Limited | Wholesale & retail | 2016 |
| P Mcevoy Cafe Ltd | Hospitality | 2018 |
| P Meeta Ltd | Health & social care | 2021 |
| P R Riley Limited | Financial services | 2009 |
| P Rhodes Engineering and Innovation Limited | Extraterritorial | 2021 |
| P S Lighting Limited | Manufacturing | 2016 |
| P S Maltby Builders Ltd | Construction | 1999 |
| P V Kaye Limited | Health & social care | 2019 |
| P W Electro Ltd | Construction | 2015 |
| P W Partnership Ltd | Information & communication | 2012 |
| P W Pro Ltd | Wholesale & retail | 2012 |
| P Waller Properties Limited | Construction | 2007 |
| P Walster Ltd | Real estate | 2015 |
| P Willetts & SON Limited | Construction | 2013 |
| P&B Consortium Ltd | Real estate | 2025 |
| P&B Property Investments Ltd | Households | 2025 |
| P&C Cleaning Services Ltd | Administrative & support | 2010 |
| P&C Plumbing Solutions Ltd | Construction | 2025 |
| P&Co. Traders Ltd | Wholesale & retail | 2021 |
| P&G Kindheart Care Agency Ltd | Administrative & support | 2026 |
| P&G Townsley Limited | Health & social care | 2019 |
| P&M Landscaping Ltd | Administrative & support | 2020 |
| P&P Alterations Ltd | Other services | 2021 |
| P&P Distribution Limited | Wholesale & retail | 2018 |
| P&R Pallets Ltd | Water & waste | 2025 |
| P&R Properties NOT Limited | Real estate | 2025 |
| P&R Properties(Notts) Ltd | Real estate | 2025 |
| P&S Electrical Services (Derby) Ltd | Construction | 2011 |
| P&S Retail Services Ltd | Wholesale & retail | 2018 |
| P-L-B-U Cookie Puppies Ltd | Agriculture & fishing | 2021 |
| P. & S. Bedding Limited | Wholesale & retail | 1984 |
| P. G. Electrical Installations Limited | Construction | 2008 |
| P. Harrison Plumbing & Heating Limited | Construction | 2016 |
| P. Hughes Construction Limited | Construction | 1987 |