| Nationwide Auto Enrolment Limited | Financial services | 2017 |
| Native Developments Ltd | Construction | 2016 |
| Natural Farms (Oxon) Limited | Manufacturing | 2003 |
| Naty's Services Ltd | Health & social care | 2024 |
| Navarino Group Limited | Financial services | 2022 |
| Navarino Services Limited | Hospitality | 2003 |
| NBC Investments Ltd | Financial services | 2019 |
| Nebuquine Limited | Professional & scientific | 2020 |
| Needle and Shed Ltd | Manufacturing | 2022 |
| Neil Bathgate Limited | Manufacturing | 2013 |
| NEM Holdings Limited | Financial services | 2020 |
| Nemo's Gymnastics Limited | Education | 2019 |
| Neneside Ltd | Construction | 2026 |
| Neovison Ecology Ltd | Professional & scientific | 2020 |
| Neovue Consulting Ltd | Information & communication | 2023 |
| Nerd 'N' Co Limited | Information & communication | 2016 |
| Nerd Central Limited | Wholesale & retail | 2022 |
| Nervesense Ltd | Health & social care | 2012 |
| Nestify Properties Ltd | Real estate | 2020 |
| Netefex Limited | Manufacturing | 2021 |
| Netful Crunkle Ltd | Real estate | 2021 |
| Netstock Operations Limited | Information & communication | 2012 |
| Netstock UK Limited | Extraterritorial | 2014 |
| Neucleia Limited | Professional & scientific | 2001 |
| Neutrino Dynamics Limited | Professional & scientific | 2011 |
| Nevara Homes Ltd | Real estate | 2021 |
| Neves Bees Limited | Professional & scientific | 2024 |
| New English Home Limited | Extraterritorial | 2013 |
| New Leaf Accounting Solutions Limited | Administrative & support | 2016 |
| New Lincoln Meadow (Standlake) Management Company Limited | Households | 2023 |
| New Looks (Oxon) Ltd | Extraterritorial | 2010 |
| New Marston Scout Hall Management Company Limited | Real estate | 2008 |
| New Mill Homes Limited | Extraterritorial | 2002 |
| New Mills Estate Management Company Limited | Households | 2010 |
| New North Partners Limited | Professional & scientific | 2020 |
| New Oxford Intelligence Ltd | Information & communication | 2023 |
| New Peking Express Ltd | Hospitality | 2023 |
| New Providence Holdings Limited | Real estate | 2020 |
| New Scaffolding (Burford) Limited | Construction | 2024 |
| New Yatt Business Centre Ltd. | Professional & scientific | 1970 |
| New Yatt Motors Limited | Wholesale & retail | 2007 |
| New Yatt Riding for the Disabled | Education | 2014 |
| Newbridge Mooring Limited | Real estate | 2011 |
| Newest Start Training Ltd | Health & social care | 2016 |
| Newland 1964 Limited | Extraterritorial | 2013 |
| Newland Construction (Oxford) Ltd | Construction | 2006 |
| Newlands (Witney) Management Company Limited | Households | 2003 |
| Newlands Vets Ltd | Professional & scientific | 2023 |
| Newman's Equipment Ltd | Real estate | 2016 |
| Newslink Witney Ltd | Wholesale & retail | 2022 |
| Newton Fellows Limited | Real estate | 2024 |
| Nexacore Ltd | Construction | 2025 |
| Nexcore Group Limited | Construction | 2025 |
| Nexfold Tech Ltd | Information & communication | 2026 |
| Next Generation Renewable Energy Ltd | Construction | 2009 |
| NGI Finance Limited | Financial services | 2005 |
| NGI Franchise Funding Limited | Financial services | 2022 |
| NHS Innovations South East Limited | Health & social care | 2004 |
| Niche Nails & Beauty Ltd | Other services | 2025 |
| Nicholas Hooper Music Limited | Information & communication | 1999 |
| Nick Allen Holdings Limited | Financial services | 2017 |
| Nick Coggins Limited | Extraterritorial | 2011 |
| Nick Jones Painting & Decorating Limited | Construction | 2019 |
| Nick Penn Fieldsports Limited | Arts & recreation | 2001 |
| Nicola Warwick Ltd | Professional & scientific | 2020 |
| Nicomerce Limited | Wholesale & retail | 2023 |
| Niep Limited | Wholesale & retail | 2014 |
| Nikora Ltd | Hospitality | 2024 |
| Nile Media Ltd | Professional & scientific | 2021 |
| Nimrod Witney Management Company Limited | Real estate | 2006 |
| Nine Sixty Three Ltd | Hospitality | 2025 |
| NIO Nextev UK Limited | Energy | 2022 |
| NIO Performance Engineering Limited | Professional & scientific | 2019 |
| Nitin Anand Ltd | Health & social care | 2013 |
| Nitron Racing Systems Limited | Manufacturing | 1998 |
| NIW Limited | Real estate | 2018 |
| Nixaccom Ltd | Real estate | 2024 |
| NJC Oxford Limited | Professional & scientific | 2013 |
| NJN Capital Limited | Professional & scientific | 2013 |
| NL Rogers Holdings Limited | Financial services | 2023 |
| NO Perditempo Ltd | Hospitality | 2024 |
| NO. 192 Oxford (Management) Limited | Hospitality | 2021 |
| NO. 192 Oxford Limited | Hospitality | 2020 |
| NO14 Wesley Walk Ltd | Hospitality | 2024 |
| Noal Limited | Information & communication | 2006 |
| Nobleid Ltd | Wholesale & retail | 2022 |
| Noest Holdings Ltd | Financial services | 2026 |
| Noise Solved Limited | Construction | 2024 |
| Nood Events Ltd | Hospitality | 2019 |
| Noodler Limited | Professional & scientific | 2017 |
| Norbury UK Investments Limited | Financial services | 2017 |
| Nordiste Ltd | Wholesale & retail | 2018 |
| North Drive Management Co. Limited | Households | 1994 |
| North Plumbing and Heating Ltd | Other services | 2017 |
| North Staffs Fleet Services Limited | Wholesale & retail | 2023 |
| Northfield Accountancy and Tax Services Limited | Professional & scientific | 2024 |
| Northfield Financial Consulting Limited | Professional & scientific | 2024 |
| Northwood (Chipping Norton) Ltd | Real estate | 2022 |
| Norton Manor Care Holdings Ltd | Health & social care | 2024 |
| Norton Shore Properties Limited | Real estate | 2023 |