| Oxford Learning LAB Limited | Arts & recreation | 2005 |
| Oxford Leather Company Limited | Manufacturing | 2025 |
| Oxford Lettings 21 Limited | Households | 2020 |
| Oxford Lettings Limited | Real estate | 2015 |
| Oxford Limited | Administrative & support | 1990 |
| Oxford Lingua Limited | Professional & scientific | 2021 |
| Oxford Links Limited | Transport & logistics | 2015 |
| Oxford Logistix Ltd | Transport & logistics | 2024 |
| Oxford Machine Intelligence Limited | Information & communication | 2010 |
| Oxford Magnets Ltd | Professional & scientific | 2026 |
| Oxford Maintenance Ltd | Construction | 2025 |
| Oxford Malayalee Samajam CIC | Other services | 2025 |
| Oxford Management & Research Limited | Professional & scientific | 1998 |
| Oxford Management College Limited | Education | 2006 |
| Oxford Management Group Limited | Professional & scientific | 1986 |
| Oxford Management Solutions Limited | Professional & scientific | 2002 |
| Oxford Management Systems Ltd | Professional & scientific | 2026 |
| Oxford Marine Technology Ltd | Professional & scientific | 2014 |
| Oxford Market Barbers Ltd | Other services | 2023 |
| Oxford Marketing Group Limited | Administrative & support | 2016 |
| Oxford Martial Arts Club Limited | Education | 2025 |
| Oxford Masonic Hall Company,Limited(The) | Hospitality | 1943 |
| Oxford Master Painters Ltd | Construction | 2022 |
| Oxford Maths School Ltd | Administrative & support | 2018 |
| Oxford Meadow Cashmere Ltd | Wholesale & retail | 2025 |
| Oxford Measured Survey Ltd | Professional & scientific | 2023 |
| Oxford Mechanical Services Limited | Construction | 2005 |
| Oxford MED Chem Ltd | Professional & scientific | 2021 |
| Oxford Media Solutions Limited | Other services | 2016 |
| Oxford Medical Accountants Limited | Professional & scientific | 2018 |
| Oxford Medical Stays Limited | Real estate | 2026 |
| Oxford Medical UK Ltd | Administrative & support | 2016 |
| Oxford Medicine and Research Limited | Professional & scientific | 2020 |
| Oxford Medinnovation Limited | Extraterritorial | 2020 |
| Oxford Medwell Academy Ltd | Administrative & support | 2019 |
| Oxford Medwell Limited | Manufacturing | 2020 |
| Oxford Men's Counselling Service Ltd. | Health & social care | 2012 |
| Oxford Mentoring and Coaching Ltd | Education | 2025 |
| Oxford Meta Limited | Professional & scientific | 2002 |
| Oxford Mindsculpt Limited | Professional & scientific | 2025 |
| Oxford Mobile Cycle Repairs Ltd | Wholesale & retail | 2011 |
| Oxford Mobile Ltd | Wholesale & retail | 2017 |
| Oxford Mobile Skips Ltd | Water & waste | 2017 |
| Oxford Mobiles & Computers Ltd | Other services | 2014 |
| Oxford Mobility Spaces Limited | Other services | 2017 |
| Oxford Molecular Medicine Academy Limited | Education | 2017 |
| Oxford Money Transfer Ltd | Financial services | 2023 |
| Oxford Multilingual Montessori Ltd | Education | 2014 |
| Oxford Mushroom Farm Ltd | Agriculture & fishing | 2025 |
| Oxford Muslim College | Education | 2014 |
| Oxford Mutual AID Limited | Health & social care | 2020 |
| Oxford Mutual Limited | Financial services | 2006 |
| Oxford Nails Limited | Other services | 2026 |
| Oxford Nanoimaging Limited | Manufacturing | 2016 |
| Oxford Nanolabs Limited | Extraterritorial | 2008 |
| Oxford Nanopore Diagnostics Limited | Professional & scientific | 2018 |
| Oxford Nanopore Technologies Holdings 2 Limited | Financial services | 2023 |
| Oxford Nanopore Technologies Holdings Limited | Financial services | 2023 |
| Oxford Nanopore Technologies PLC | Professional & scientific | 2005 |
| Oxford Nanosystems Ltd | Manufacturing | 2011 |
| Oxford Natural Resources Limited | Wholesale & retail | 2000 |
| Oxford Neurodiversity Services Ltd | Health & social care | 2023 |
| Oxford Neurosciences Limited | Health & social care | 2020 |
| Oxford New Work Trust Ltd. | Real estate | 1985 |
| Oxford Newprime Limited | Information & communication | 2019 |
| Oxford News Hub Ltd | Information & communication | 2026 |
| Oxford North Canalside Limited | Construction | 2020 |
| Oxford North Central Limited | Construction | 2020 |
| Oxford North Eastside Limited | Construction | 2020 |
| Oxford North Estates Limited | Construction | 2020 |
| Oxford North Hotels Limited | Construction | 2020 |
| Oxford North Limited | Construction | 2020 |
| Oxford North Management Limited | Construction | 2020 |
| Oxford North Parking Limited | Construction | 2020 |
| Oxford North Peartree Limited | Construction | 2020 |
| Oxford North Science Limited | Construction | 2020 |
| Oxford Numerology Academy | Education | 2026 |
| Oxford Numerology Press | Education | 2026 |
| Oxford Numerology Research | Education | 2026 |
| Oxford Numerology Society | Education | 2023 |
| Oxford Nutrition Clinic Ltd | Health & social care | 2023 |
| Oxford Oak Ltd | Manufacturing | 2013 |
| Oxford Oak Structures Limited | Construction | 2024 |
| Oxford OFF Licence Ltd | Wholesale & retail | 2022 |
| Oxford Offshore Limited | Professional & scientific | 2025 |
| Oxford Omega Limited | Real estate | 2025 |
| Oxford Omics Ltd | Other services | 2020 |
| Oxford Oncology Clinic Limited | Health & social care | 2020 |
| Oxford One Ltd. | Arts & recreation | 2003 |
| Oxford Online English Ltd | Education | 2019 |
| Oxford Online School Ltd | Education | 2020 |
| Oxford Oral and Maxillofacial Surgery Limited | Extraterritorial | 2013 |
| Oxford Oral Surgery Limited | Health & social care | 2013 |
| Oxford Oralmax Ltd | Administrative & support | 2016 |
| Oxford Orbital Limited | Information & communication | 2022 |
| Oxford Organix Limited | Wholesale & retail | 2002 |
| Oxford Orthopaedic Consulting Ltd | Professional & scientific | 2014 |
| Oxford Orthopaedic Solutions Ltd. | Administrative & support | 2019 |
| Oxford Orthopaedic Technology Ltd | Professional & scientific | 2014 |
| Oxford Orthotic Clinic Limited | Health & social care | 2012 |