| Novo Onboard Retail Limited | Information & communication | 2019 |
| Novocom Systems Limited | Extraterritorial | 2012 |
| Novus Capital Ltd | Professional & scientific | 2020 |
| Novus Financial Services Limited | Financial services | 2011 |
| Nowt Health Limited | Manufacturing | 2025 |
| NOWT2WEAR Ltd | Wholesale & retail | 2021 |
| Nozi Nails Ltd | Other services | 2024 |
| Npce Ltd | Professional & scientific | 2023 |
| NRL Events Limited | Arts & recreation | 2025 |
| NRW IT Ltd | Other services | 2018 |
| NSI Medical Ltd | Health & social care | 2021 |
| NTG Business Consultants Limited | Professional & scientific | 2019 |
| NTS Investment Ventures Limited | Information & communication | 2016 |
| NTS Ventures Limited | Information & communication | 2019 |
| NU Developments Limited | Construction | 2020 |
| NU Studios L&M Limited | Other services | 2022 |
| Nu-Space Group Limited | Financial services | 2026 |
| Nu-Space Harrogate Limited | Real estate | 2026 |
| Nuay Ltd | Health & social care | 2025 |
| Nugel Limited | Manufacturing | 2008 |
| Nugen Talent Limited | Administrative & support | 2025 |
| Nuggets Insight Ltd | Professional & scientific | 2026 |
| Number 1 Surgical Healthcare Limited | Health & social care | 2024 |
| Number 1 Westcliffe Terrace (Property Management) Limited | Real estate | 1998 |
| Number 14 Management Limited | Households | 2012 |
| Number 2 West Grove Road Property Management Company Limited | Households | 2013 |
| Number 34 Park Cross Street LLP | | 2013 |
| Number 41 Limited | Professional & scientific | 2005 |
| Number One Dragon Parade Management Company Limited | Households | 2007 |
| Nuovo Living Limited | Construction | 2017 |
| Nutrus Ltd | Wholesale & retail | 2025 |
| NVP Services Ltd | Construction | 2025 |
| Nwconsultancy Ltd | Professional & scientific | 2015 |
| NY Logistics Limited | Transport & logistics | 2025 |
| NY Property Consultants Ltd | Real estate | 2025 |
| NY Residential Ltd | Real estate | 2016 |
| Nynet 100 Limited | Information & communication | 2012 |
| Nynet Limited | Information & communication | 2007 |
| Nynet Public Sector Limited | Information & communication | 2026 |
| Nyon Group Ltd | Professional & scientific | 2015 |
| NZN Limited | Construction | 2023 |
| O'Connor Chiropractic Ltd | Other services | 2010 |
| O'Neil's Recruitment.Com Ltd | Administrative & support | 2013 |
| O-Consult Ltd | Administrative & support | 2010 |
| O.W Performance Ltd | Professional & scientific | 2025 |
| OA Plastering Ltd | Construction | 2025 |
| Oak Advisory Group Ltd | Construction | 2025 |
| Oak Beck Consulting Ltd | Professional & scientific | 2021 |
| Oak Garth (Burnt Yates) Management Limited | Households | 2020 |
| Oak Meadow Montessori Limited | Education | 2026 |
| Oakdale Advisory Limited | Professional & scientific | 2026 |
| Oakdale Centre CIC | Education | 2016 |
| Oakdale Consulting Group Ltd | Professional & scientific | 2023 |
| Oakdale Therapies Ltd | Education | 2019 |
| Oakdene Limited | Financial services | 2017 |
| Oakfield 10 Limited | Professional & scientific | 2018 |
| Oakleyhomeandgardens Ltd | Construction | 2026 |
| Oaks Electrical Harrogate Ltd | Construction | 2022 |
| Oakshot Limited | Extraterritorial | 2025 |
| Oakstone Property Developments Limited | Real estate | 2004 |
| Oakwood Document Storage Ltd | Administrative & support | 2020 |
| OAS1S Ltd | Extraterritorial | 2019 |
| Oates Residential Limited | Real estate | 2023 |
| Oatlands Accounting Limited | Professional & scientific | 2002 |
| Occasional Limited | Wholesale & retail | 2024 |
| OCD Cleaning Services (Harrogate) Limited | Administrative & support | 2021 |
| Ocean and Alpine Limited | Education | 2010 |
| Ocean Bioplastics Ltd | Manufacturing | 2026 |
| Ocean Crown Otley Limited | Hospitality | 2020 |
| Ocean Facilities Management Limited | Extraterritorial | 2025 |
| Ocean Kind Products Limited | Manufacturing | 2021 |
| Ocean Scientific Limited | Extraterritorial | 2025 |
| Ocean Spray Limited | Extraterritorial | 2011 |
| OCH Management Services Limited | Administrative & support | 2016 |
| Ocol Estates Ltd | Real estate | 2021 |
| Ocol Plumbing and Heating Ltd | Construction | 2022 |
| Octagon Court (Harrogate) Limited | Households | 1986 |
| Oculance Ltd | Health & social care | 2024 |
| Oculus Synergy Limited | Professional & scientific | 2026 |
| Oculus Wealth Management (Aberdeen) Limited | Financial services | 2026 |
| Oculus Wealth Management (Aberdovey) Limited | Financial services | 2023 |
| Oculus Wealth Management (Adventus) Limited | Financial services | 2024 |
| Oculus Wealth Management (Birmingham) Limited | Financial services | 2021 |
| Oculus Wealth Management (Bradford on Avon) Limited | Financial services | 2019 |
| Oculus Wealth Management (Bristol) Limited | Financial services | 2023 |
| Oculus Wealth Management (Bromsgrove) Limited | Financial services | 2025 |
| Oculus Wealth Management (Cambridge) Limited | Financial services | 2022 |
| Oculus Wealth Management (Central London) Limited | Financial services | 2022 |
| Oculus Wealth Management (Cheshire) Limited | Financial services | 2021 |
| Oculus Wealth Management (Chilterns) Limited | Financial services | 2022 |
| Oculus Wealth Management (City) Limited | Financial services | 2020 |
| Oculus Wealth Management (Consulting) Limited | Financial services | 2023 |
| Oculus Wealth Management (Coppice) Limited | Financial services | 2023 |
| Oculus Wealth Management (Decem) Limited | Financial services | 2024 |
| Oculus Wealth Management (DEP) Limited | Financial services | 2025 |
| Oculus Wealth Management (Dulwich) Limited | Financial services | 2025 |
| Oculus Wealth Management (East Dorset) Limited | Financial services | 2020 |
| Oculus Wealth Management (East Sussex) Limited | Financial services | 2019 |
| Oculus Wealth Management (Edinburgh and East) Limited | Financial services | 2026 |
| Oculus Wealth Management (Edinburgh and West) Limited | Financial services | 2026 |