| Myrie Rail Services Ltd | Other services | 2016 |
| N Dugmore Plumbing and Heating Ltd | Construction | 2022 |
| NAB Change Consulting Ltd | Professional & scientific | 2022 |
| Nationsurvey Ltd | Professional & scientific | 2022 |
| Nationsurveyuk LLP | | 2026 |
| Nationwide Surveying Limited | Other services | 2019 |
| Naylor & Co Properties Ltd | Real estate | 2024 |
| NDT Access Solutions Ltd | Professional & scientific | 2011 |
| Near MAX Ltd | Information & communication | 2014 |
| New Amersham Holdings 2 Limited | Professional & scientific | 2026 |
| New Amersham Holdings Limited | Health & social care | 2020 |
| New Chinnor Pump Ltd | Information & communication | 2025 |
| New Level London Ltd | Wholesale & retail | 2015 |
| Nicand Limited | Real estate | 2001 |
| Nicer Media Limited | Information & communication | 2003 |
| Nippyluv Ltd | Wholesale & retail | 2026 |
| Nstart LLP | | 2022 |
| Nvard Ltd | Information & communication | 2016 |
| O'Toole Plumbing and Heating Limited | Construction | 2019 |
| Oak Hill GAS Limited | Construction | 2023 |
| Oasis Pro Limited | Information & communication | 2014 |
| Orasi Services Ltd | Health & social care | 2024 |
| Oscar AI Limited | Information & communication | 2025 |
| Oscat Solutions Ltd | Information & communication | 2025 |
| Oxford Strategic Learning Ltd | Professional & scientific | 2021 |
| Oxhand Limited | Construction | 2018 |
| Oxnard Homes Ltd | Real estate | 2025 |
| Paddock Edge Ltd | Households | 2023 |
| Paddocks Project Ltd | Wholesale & retail | 2013 |
| Palmcrown Properties Limited | Real estate | 1995 |
| Partridges Accountancy Services Limited | Professional & scientific | 2013 |
| Paynes Grey Limited | Arts & recreation | 2017 |
| Payrollcafe Limited | Professional & scientific | 2002 |
| PB Painting Services Ltd | Construction | 2011 |
| Peardrop Design Systems Limited | Professional & scientific | 2017 |
| Pedantech Ltd | Information & communication | 2026 |
| Pergamon Finance Corporation Limited | Financial services | 2012 |
| Petano's Ltd | Other services | 2025 |
| Phaia Wellness Limited | Other services | 2025 |
| Pharmacing and Care Ltd | Administrative & support | 2022 |
| Pictures Inc Ltd | Professional & scientific | 2006 |
| Pitch Perfect Sales Ltd | Professional & scientific | 2025 |
| PLG Windows Limited | Construction | 2008 |
| Portable HR Solutions Limited | Administrative & support | 2009 |
| Priority Service Ltd | Administrative & support | 2013 |
| Professional Profile Limited | Education | 2017 |
| Progressive Property Network Oxford Ltd | Real estate | 2023 |
| Propertq Limited | Construction | 2006 |
| Property Accounting & Tax Solutions Ltd | Professional & scientific | 2022 |
| Property Investment School Ltd | Administrative & support | 2025 |
| Prosource UK Investments Limited | Real estate | 2017 |
| Publishing Consultancy Group UK Ltd | Professional & scientific | 2019 |
| Pure Interiors Limited | Manufacturing | 2022 |
| Quantum Investment & Wealth Management Limited | Administrative & support | 2010 |
| R Monk Kitchens & Bedrooms Ltd | Construction | 2019 |
| R.J. Rose & SON Limited | Agriculture & fishing | 1983 |
| Racing Reality Limited | Professional & scientific | 2019 |
| Raixon Ltd | Information & communication | 2024 |
| Raleigh Financial Limited | Financial services | 2022 |
| Raworth Construction Limited | Construction | 2014 |
| Raynet-Uk | Administrative & support | 1992 |
| Recom Asphalt Solutions Limited | Construction | 2015 |
| Red Anca Ltd | Construction | 2023 |
| Red Star Digital Limited | Information & communication | 2010 |
| Regent FOX Estate Agents Ltd | Real estate | 2026 |
| Remote Tech Solutions Ltd | Information & communication | 2025 |
| Renewed Eco Shop Ltd | Wholesale & retail | 2022 |
| Resilience and Cyber Services Ltd | Information & communication | 2024 |
| Revuu Limited | Information & communication | 2024 |
| Rhodes Financial Group Limited | Financial services | 2021 |
| Rhodes Financial Limited | Professional & scientific | 2021 |
| Richard Bennett and Associates Limited | Professional & scientific | 2013 |
| Richard Milner Limited | Wholesale & retail | 1982 |
| Richmond Trading Limited | Other services | 2012 |
| Ridgemount Healthcare Ltd | Wholesale & retail | 2021 |
| Ridgeway Security Systems Ltd | Administrative & support | 2023 |
| RJP Group Holdings Ltd | Real estate | 2019 |
| RJS Interiors (London) Limited | Administrative & support | 2002 |
| RL Plumbing and GAS Ltd | Construction | 2025 |
| RLE Investments LP | | 2009 |
| Robanna Limited | Real estate | 2010 |
| Robert Pettingell Osteopath Limited | Health & social care | 2004 |
| Robust Technical Systems Limited | Extraterritorial | 2015 |
| Rocks Corporation Ltd | Manufacturing | 2015 |
| Romyn Enterprises Limited | Hospitality | 2013 |
| Rookery Farm Operations Ltd | Agriculture & fishing | 1996 |
| Rosib Ltd | Construction | 2025 |
| Rsskks Limited | Real estate | 2018 |
| RVB Holding Company Limited | Professional & scientific | 1998 |
| RVB Investments | Financial services | 1992 |
| S Bains Management Ltd | Professional & scientific | 2019 |
| Sanderum Limited | Extraterritorial | 2023 |
| Sanderum Motorsport Simulators Limited | Wholesale & retail | 2023 |
| Sapphire Group Developments Ltd | Construction | 2024 |
| Sapphire Group Oxfordshire Ltd | Professional & scientific | 2023 |
| Satsuki Oxford Limited | Hospitality | 2019 |
| SG Precise Carpentry Ltd | Manufacturing | 2025 |
| Shepherds Crook Limited | Hospitality | 2016 |
| Silver Moon Hair Ltd | Other services | 2021 |
| Simple Benefits LLP | | 2015 |