| New Student Living Ltd | Construction | 2017 |
| New Valleys Congleton Limited | Hospitality | 2023 |
| Newcorp Computer Services Limited | Information & communication | 1997 |
| Newcorp Management Services Limited | Real estate | 2002 |
| Newdawn Data Services Limited | Information & communication | 1998 |
| Newfield Automation Limited | Information & communication | 1989 |
| Newfield Holdings Limited | Information & communication | 1998 |
| Next Brick Limited | Real estate | 2023 |
| Next Steps Physiotherapy Limited | Health & social care | 2020 |
| Nextgen Products Ltd | Wholesale & retail | 2019 |
| NHD Property Ltd | Real estate | 2019 |
| Nick Stuart Ltd | Information & communication | 2012 |
| Nightingale Land Investments Limited | Real estate | 2026 |
| Nightingales Property Services Limited | Real estate | 1999 |
| Ninedash Limited | Administrative & support | 2020 |
| Nineties Group Limited | Financial services | 2025 |
| Nittle Limited | Professional & scientific | 2013 |
| NJG Property Limited | Real estate | 2025 |
| Nlea Ltd | Information & communication | 2024 |
| NLG Analytical Limited | Extraterritorial | 2006 |
| NMC Dermatology Limited | Health & social care | 2012 |
| NO 12 Foundation C.I.C. | Other services | 2025 |
| Nodex Limited | Information & communication | 2013 |
| Nontodo Limited | Professional & scientific | 2014 |
| Nooco Digital Ltd | Information & communication | 2022 |
| Norbridge Limited | Real estate | 2010 |
| Nortek Educational Furniture Limited | Manufacturing | 2020 |
| Nortek Electronic Circuits Limited | Manufacturing | 1978 |
| Nortek Electronic Holdings Limited | Extraterritorial | 2008 |
| Nortek Industrial Furniture Limited | Manufacturing | 2020 |
| Nortek Technical Furniture Systems Limited | Wholesale & retail | 2015 |
| North Rode Timber Company Limited | Wholesale & retail | 1941 |
| North Staffs Rentals Limited | Real estate | 2014 |
| North West IP Services Ltd | Professional & scientific | 2026 |
| North West Spirits Limited | Wholesale & retail | 2017 |
| Northern Capital Holdings Limited | Health & social care | 2018 |
| Northern Housing Association Limited | Real estate | 2019 |
| Northern Keys Ltd | Real estate | 2016 |
| Northern Visa Medicals Limited | Health & social care | 2020 |
| Northwest Land & Property Limited | Real estate | 2021 |
| Northwest Plant Agri Limited | Wholesale & retail | 2017 |
| Northwest Tractors Ltd | Extraterritorial | 2018 |
| Northwich Vapour Limited | Wholesale & retail | 2024 |
| Notionxintelligence Ltd | Information & communication | 2025 |
| Nova Interior Contracts Limited | Construction | 1993 |
| Novak Limited | Construction | 1992 |
| Nowell Court Management Limited | Households | 1981 |
| NQA Awarding Organisation Ltd | Public administration | 2025 |
| NRC Enterprises Limited | Real estate | 2002 |
| NSC Ltd | Information & communication | 2025 |
| Nuchem Consultants Ltd | Professional & scientific | 2009 |
| Nulisa Ltd | Real estate | 2019 |
| NUM Technology Ltd | Information & communication | 2016 |
| Number One Studio Ltd | Professional & scientific | 2004 |
| Nutriadvance Limited | Wholesale & retail | 2025 |
| NW EYE Specialist Centre Ltd | Health & social care | 2021 |
| NW Intelligence Ltd | Information & communication | 2021 |
| NWC Construction Ltd | Construction | 2011 |
| O & T Shop Fitting Limited | Construction | 2024 |
| O&S Hospitality Ltd | Hospitality | 2025 |
| O&T Construction Limited | Construction | 2023 |
| O'Rourke Engineering Technical & Support Services Limited | Professional & scientific | 2008 |
| Oak & Ember Research Limited | Professional & scientific | 2025 |
| Oak Tree Training Limited | Other services | 2008 |
| Oakchapel Ltd | Professional & scientific | 2021 |
| Oakfield Inns Ltd | Hospitality | 2019 |
| Oaklyn Supplies Limited | Wholesale & retail | 1997 |
| Oakstone Electrical Limited | Construction | 2009 |
| Oakwood Home Projects Ltd | Construction | 2023 |
| Oasis Consult Limited | Other services | 2010 |
| OBC Investments Limited | Real estate | 2025 |
| OBC Plastering Limited | Construction | 2025 |
| Objective Intuition Limited | Information & communication | 1988 |
| OC Welding Ltd | Manufacturing | 2025 |
| Ocean Breeze Property Limited | Wholesale & retail | 2018 |
| Ocean Courage Limited | Financial services | 2019 |
| Ocean Group Developments Limited | Construction | 2018 |
| Ocean Group Homes Ltd | Extraterritorial | 2018 |
| Ocean Group Management Ltd | Professional & scientific | 2020 |
| OH Lala Crepe Limited | Extraterritorial | 2024 |
| OH Shoot! Plants Ltd | Wholesale & retail | 2024 |
| OK Electrical Services Ltd | Construction | 2024 |
| Oldom Ltd | Hospitality | 2020 |
| Oldtip Limited | Professional & scientific | 2013 |
| Olenol Limited | Manufacturing | 1989 |
| Olimojo Ltd | Extraterritorial | 2020 |
| Olive Bear Ltd | Other services | 2021 |
| Olives & Herbs Ltd | Hospitality | 2024 |
| Olivo Property Limited | Professional & scientific | 2010 |
| Olympus Enterprises Ltd | Wholesale & retail | 2020 |
| OM Commercial Ltd | Real estate | 2023 |
| Ondigital Limited | Information & communication | 2013 |
| One Call Contractors (Shropshire) Limited | Construction | 2025 |
| One for Instrumentation Ltd | Manufacturing | 2003 |
| One MAN Gang Ltd | Information & communication | 2025 |
| ONE2ONE Construction Solutions Limited | Professional & scientific | 2018 |
| Oneflow Collective Ltd | Information & communication | 2025 |
| Online Rhino Ltd | Wholesale & retail | 2021 |
| Onwigo Ltd | Information & communication | 2024 |
| Onyx Steel Limited | Administrative & support | 2020 |