| Oswell Property Limited | Real estate | 2021 |
| Otlo Brands Ltd | Other services | 2023 |
| Otnss Ltd | Information & communication | 2022 |
| Otwell Homes Limited | Real estate | 2024 |
| OUR GUY Ltd | Wholesale & retail | 2024 |
| OUR Home OUR Life Limited | Real estate | 2014 |
| Outbio UK Ltd | Administrative & support | 2020 |
| Oval Hire Ltd | Administrative & support | 2025 |
| Overseas Bricks Investments Ltd | Real estate | 2022 |
| Overture Limited | Wholesale & retail | 1989 |
| OWP Investments Ltd | Extraterritorial | 2017 |
| OX Barton Village Road Limited | Real estate | 2023 |
| OX Designers Ltd | Arts & recreation | 2014 |
| OX Services Ltd | Administrative & support | 2016 |
| Oxandia Ltd | Professional & scientific | 2006 |
| Oxbridgeedu & Culture Limited | Education | 2024 |
| Oxen Design Limited | Professional & scientific | 2015 |
| OXF Group Limited | Professional & scientific | 2020 |
| Oxford Television Limited | Information & communication | 2011 |
| Oxford 3D Limited | Professional & scientific | 2020 |
| Oxford 4X4 Ltd | Wholesale & retail | 2019 |
| Oxford A40 Motors Ltd | Wholesale & retail | 2019 |
| Oxford Agricultural Consultants Limited | Professional & scientific | 1984 |
| Oxford AI School Limited | Education | 2026 |
| Oxford App Development Ltd | Information & communication | 2019 |
| Oxford Applied Research Limited | Manufacturing | 1978 |
| Oxford Applied Training Ltd | Professional & scientific | 2015 |
| Oxford Architectural Design Limited | Professional & scientific | 2011 |
| Oxford Audio Limited | Arts & recreation | 2013 |
| Oxford Aviation Limited | Wholesale & retail | 1998 |
| Oxford Biovault Limited | Professional & scientific | 2026 |
| Oxford Bone Infection Consultancy Limited | Professional & scientific | 2016 |
| Oxford Building Contractors Limited | Construction | 2022 |
| Oxford Carriers Holdings Ltd | Financial services | 2020 |
| Oxford Carriers Ltd | Transport & logistics | 2014 |
| Oxford Chauffeur Service Ltd | Transport & logistics | 2018 |
| Oxford City Transport Limited | Transport & logistics | 2024 |
| Oxford Conservation Limited | Extraterritorial | 2013 |
| Oxford Consultancy Partnership Limited | Public administration | 2007 |
| Oxford Consulting Engineers Ltd | Professional & scientific | 2013 |
| Oxford Creativity Limited | Professional & scientific | 1999 |
| Oxford Devices Ltd | Manufacturing | 1997 |
| Oxford Digital Limited | Professional & scientific | 2005 |
| Oxford Downs Cricket Club CIC | Arts & recreation | 2024 |
| Oxford Eco Centre Ltd | Real estate | 2019 |
| Oxford Electrical Installations Ltd | Construction | 2017 |
| Oxford Electrical Specialists Ltd | Construction | 2022 |
| Oxford Energy Academy Limited | Education | 2011 |
| Oxford English Camps Ltd | Education | 2024 |
| Oxford Environmental Safety Consultancy Ltd | Administrative & support | 2009 |
| Oxford Facilities Ltd | Administrative & support | 2024 |
| Oxford Fire and Security Ltd | Administrative & support | 2021 |
| Oxford Fire and Security Services Ltd | Administrative & support | 2021 |
| Oxford Fire and Security Systems Ltd | Administrative & support | 2021 |
| Oxford Fire Extinguishers Ltd | Public administration | 2022 |
| Oxford Flow Limited | Professional & scientific | 2015 |
| Oxford Garden Design Limited | Professional & scientific | 2012 |
| Oxford Gates and Automation Limited | Administrative & support | 2000 |
| Oxford Gifted and Talented Education Ltd | Education | 2016 |
| Oxford Glass & Glazing Systems Limited | Manufacturing | 2008 |
| Oxford Glasshouse Limited | Construction | 2014 |
| Oxford Global Partnership Limited | Professional & scientific | 2014 |
| Oxford Homes (Aston) Limited | Construction | 2014 |
| Oxford Homes (Brackley) LLP | | 2007 |
| Oxford Homes (Development) Limited | Construction | 2002 |
| Oxford Homes (Kidlington) LLP | | 2007 |
| Oxford Homes Residential Ltd | Construction | 2014 |
| Oxford Homestay Limited | Hospitality | 2014 |
| Oxford Influential Limited | Professional & scientific | 2001 |
| Oxford International College of Beauty Limited | Education | 2005 |
| Oxford Leaders Limited | Professional & scientific | 2010 |
| Oxford Live Productions Ltd | Arts & recreation | 2021 |
| Oxford Lymphoedema Practice Limited | Health & social care | 2013 |
| Oxford Media Factory Limited | Information & communication | 2013 |
| Oxford Medical Products Limited | Professional & scientific | 2016 |
| Oxford Medtech Consulting Limited | Professional & scientific | 2017 |
| Oxford Migraine Practice Limited | Health & social care | 2016 |
| Oxford Parklands Limited | Construction | 1985 |
| Oxford Performance Autos Limited | Manufacturing | 2024 |
| Oxford Phoenix Innovation Limited | Extraterritorial | 2014 |
| Oxford Plus Holdings Limited | Financial services | 2025 |
| Oxford Plus Properties Limited | Real estate | 2025 |
| Oxford Pools Services Limited | Construction | 2015 |
| Oxford Postpartum Medical Practice Ltd | Health & social care | 2024 |
| Oxford Rally and Restoration Services Ltd | Manufacturing | 2023 |
| Oxford Rally Services Ltd | Wholesale & retail | 2023 |
| Oxford Research and Development Limited | Professional & scientific | 2020 |
| Oxford School of Ballet Limited | Education | 2023 |
| Oxford Security Limited | Administrative & support | 2019 |
| Oxford Security Services Limited | Administrative & support | 2018 |
| Oxford Strategy LAB Ltd | Professional & scientific | 2025 |
| Oxford Surveying Services Limited | Professional & scientific | 2012 |
| Oxford Swimming Academy Ltd. | Education | 2016 |
| Oxford Teacher Services Limited | Administrative & support | 2014 |
| Oxford Tube & Fittings Limited | Administrative & support | 2017 |
| Oxford Van Centre Limited | Wholesale & retail | 2023 |
| Oxford Voice Workshop Limited | Professional & scientific | 2025 |
| Oxford Wine Holdings Ltd | Financial services | 2025 |
| Oxfordpoolbuilding Ltd | Construction | 2015 |
| Oxfordpoolchemicals Ltd | Construction | 2015 |