| NSS Corp Limited | Information & communication | 2007 |
| Nudge Advisory Limited | Administrative & support | 2006 |
| Nuha Footwear Ltd | Wholesale & retail | 2007 |
| Nuneaton Hose & Fittings Limited | Manufacturing | 1995 |
| Nuvias UC Holdings Limited | Financial services | 2022 |
| O M I Enterprises Limited | Wholesale & retail | 2005 |
| O'Reilly Decorators Limited | Construction | 1995 |
| Olamina Ltd | Real estate | 2022 |
| Oliver Family Estates Limited | Real estate | 2002 |
| Oliver Liggins Limited | Professional & scientific | 2006 |
| Omeetoo Combined Arts C.I.C. | Education | 2004 |
| One Dental Limited | Health & social care | 2006 |
| One Stop Discount Shop Ltd | Wholesale & retail | 2019 |
| Orbitech Digital Technologies Ltd | Information & communication | 2024 |
| Oriental Star (2025) Limited | Hospitality | 2025 |
| Original Dynamic Limited | Professional & scientific | 1993 |
| Oxford Commercial Services Limited | Administrative & support | 1988 |
| Oxford Corporate Services Limited | Administrative & support | 1986 |
| Oxford Estates Limited | Hospitality | 1985 |
| Oxley Churchill Limited | Professional & scientific | 2025 |
| O’Brien Energy Limited | Construction | 2023 |
| P a Beaumont Limited | Health & social care | 2002 |
| P J Tooth Limited | Construction | 2003 |
| P L M C S Limited | Professional & scientific | 2004 |
| Packet Projects Ltd | Extraterritorial | 2005 |
| Paper Scanners Limited | Extraterritorial | 2006 |
| Pasargadae Limited | Other services | 2017 |
| Paul Bloxham Ltd | Wholesale & retail | 2004 |
| Pelco Design Limited | Professional & scientific | 1995 |
| Perceptisys Limited | Information & communication | 2005 |
| Performance Time Ltd | Wholesale & retail | 2003 |
| Permanent Bear Limited | Professional & scientific | 2003 |
| Pertemps Network Catering Limited | Administrative & support | 1992 |
| Petit Forestier UK Limited | Administrative & support | 1983 |
| Phil Ingle Associates Ltd | Professional & scientific | 2001 |
| Phil Popham Consultancy Limited | Professional & scientific | 2021 |
| Philip Antrobus Limited | Professional & scientific | 1991 |
| Philip Brown Associates Limited | Administrative & support | 2007 |
| Pickering Metals Limited | Extraterritorial | 1993 |
| Pillinger Tennis Limited | Arts & recreation | 2007 |
| Pizza 20 Ltd | Hospitality | 2018 |
| Pjmc Limited | Professional & scientific | 2002 |
| Planscapes (Midlands) Limited | Wholesale & retail | 1980 |
| Plant 3 Properties Ltd | Real estate | 2005 |
| Platinum Mind Therapy Ltd | Health & social care | 2024 |
| Porton Developments Limited | Real estate | 2004 |
| Powerscribe Internet Solutions Limited | Information & communication | 2003 |
| Premium Facilities Services Ltd | Administrative & support | 2025 |
| Prestige Plastics Medical Limited | Manufacturing | 2004 |
| Pro Enviro Limited | Administrative & support | 1994 |
| Probity Advocacy Ltd | Professional & scientific | 2005 |
| Proctor & Sons Commercial Lettings Limited | Real estate | 2008 |
| Proforce Property Limited | Professional & scientific | 2002 |
| Programme Vision Ltd | Professional & scientific | 2008 |
| Property Pushers Limited | Real estate | 2003 |
| PSW Paper & Print Limited | Manufacturing | 2005 |
| PT Engineers Holdings Ltd | Manufacturing | 1965 |
| PT Engineers Limited | Manufacturing | 2002 |
| PT Griffiths Transport Limited | Transport & logistics | 2004 |
| Puddleducks & P.O.S.H. Limited | Other services | 2006 |
| Pugh's Haulage Limited | Transport & logistics | 2004 |
| Purple PIG Limited | Real estate | 2004 |
| Purple Triangle Ltd | Information & communication | 2002 |
| PWB Design & Build Limited | Construction | 1996 |
| Quinn Financial Solutions Ltd | Financial services | 2018 |
| R B Consulting (Coventry) Limited | Construction | 2023 |
| R C Phillips Garden Design & Landscaping Ltd | Construction | 2019 |
| R D Griffin Building Services Limited | Construction | 2002 |
| R J Joinery (Rugby) Limited | Manufacturing | 2003 |
| R. Hancock Limited | Construction | 1995 |
| R.C.Grant Carpentry Limited | Construction | 2003 |
| R.F. Exhibitions Limited | | 1979 |
| R.J. Kingston Engineering Limited | Manufacturing | 1974 |
| Racoon International Holdings Limited | Professional & scientific | 2006 |
| Ragley Estate Meats Limited | Wholesale & retail | 2006 |
| Rainbows Carpets Limited | Wholesale & retail | 2002 |
| RAJ Khanna Associates Limited | Education | 2001 |
| RAM Wines & Spirits Limited | Wholesale & retail | 2003 |
| Ratcliffe Medical Services Limited | Health & social care | 1992 |
| RBH Associates Limited | Professional & scientific | 2007 |
| Rbit Hospitality Limited | Hospitality | 2025 |
| Rcma Agricultural Storage Limited | Agriculture & fishing | 2024 |
| Real Point Design Limited | Professional & scientific | 2001 |
| Reardon Associates Ltd | Professional & scientific | 2002 |
| Recovery Master Limited | Professional & scientific | 2003 |
| RECRUIT4TALENT Limited | Administrative & support | 2011 |
| Refrigerated Dispense Services Limited | Professional & scientific | 2003 |
| Regent Street Castle Ltd | Hospitality | 2022 |
| Residents Management Company (the Hurlingham) Limited | Households | 2026 |
| Revitalise Blind Cleaning Ltd | Other services | 2017 |
| Revo SM Group Ltd | Information & communication | 2015 |
| Reways UK Ltd | Wholesale & retail | 1968 |
| Rick's Bar Limited | | 1983 |
| Rigby Real Estate Limited | Financial services | 2017 |
| Riverside Veterinary Centre Limited | Professional & scientific | 2004 |
| RJ Garner Limited | Manufacturing | 2002 |
| RJ Panels Limited | Manufacturing | 2007 |
| RKW Investments Limited | Real estate | 2021 |
| Robberts Consulting Limited | Professional & scientific | 2007 |
| Robin Coleman Leather Technology Limited | Manufacturing | 2007 |