| NER One Limited | Financial services | 2021 |
| NER Two Limited | Professional & scientific | 2021 |
| Nerds Nutrition Ltd | Wholesale & retail | 2026 |
| Nests & Founds Ltd | Construction | 2024 |
| Netside Properties Limited | Real estate | 2005 |
| Neuroglimmer Ltd | Health & social care | 2025 |
| Newbould Sports Coaching LLP | | 2014 |
| Newburn (LSA Properties) Ltd | Real estate | 2008 |
| Newbury Commercial Ltd | Real estate | 2016 |
| Newcastle Communications Limited | Professional & scientific | 2003 |
| Newline Estates Ltd | Real estate | 2013 |
| Newstead Management Company Limited | Households | 1989 |
| Next Level Creative Limited | Professional & scientific | 2025 |
| Nextstar Limited | Extraterritorial | 2015 |
| Nexus Investigations Limited | Administrative & support | 2019 |
| Nexus Missing Persons Ltd | Administrative & support | 2025 |
| Nicholas Parker Property Ltd | Real estate | 2025 |
| Nicholas Yates Management Ltd | Arts & recreation | 2018 |
| Nick Bingham Limited | Construction | 2014 |
| Nick Wall Nutrition Ltd | Health & social care | 2020 |
| Nicola Morris Limited | Administrative & support | 2004 |
| Nidu Property Ltd | Real estate | 2026 |
| Niknatamy Limited | Real estate | 2003 |
| Nimbus Secure Solutions Limited | Information & communication | 2025 |
| Nine Dots Technology Ltd | Information & communication | 2016 |
| Ninkasi Systems Limited | Information & communication | 2018 |
| Nirmal Darbar Infrastructure Limited | Professional & scientific | 2022 |
| NJ Consulting Group Limited | Information & communication | 2017 |
| NJD Couriers & Logistics Ltd | Transport & logistics | 2025 |
| NJP Energy Ltd | Professional & scientific | 2022 |
| NJR Property Ltd | Households | 2022 |
| NO 2 ST George's Management Company Limited | Administrative & support | 2002 |
| NO. 37 Ltd | Wholesale & retail | 2020 |
| Norden Lodge Management Company Limited | Households | 2004 |
| North West Discount Pet Foods Ltd | Wholesale & retail | 2004 |
| North West Pathology Limited | Professional & scientific | 2018 |
| Northampton Claims Limited | Other services | 2025 |
| Northern Monkey Creative Media Limited | Information & communication | 2012 |
| Northern Point Tipi Ltd | Hospitality | 2025 |
| Northgate Flat Services Limited | Households | 1973 |
| Northling Music Limited | Arts & recreation | 2021 |
| Northstar Care and Support Ltd | Health & social care | 2026 |
| Northwest Portable Toilet Company Limited | Other services | 2016 |
| Norton Scientific Limited | Manufacturing | 2006 |
| Notelos Limited | Information & communication | 2017 |
| Nothing Else Matters Music Ltd | Information & communication | 2019 |
| Nourish Labs Limited | Health & social care | 2025 |
| Nova Apparel Limited | Wholesale & retail | 2020 |
| Nova KC Limited | Wholesale & retail | 2020 |
| Novabay Limited | Professional & scientific | 2005 |
| Novelette Novalis Limited | Manufacturing | 2009 |
| Novikov Spain Ltd | Hospitality | 2023 |
| Noye Construction Ltd | Construction | 2020 |
| Noye Contracting Ltd | Construction | 2020 |
| NP Nutrition Ltd | Wholesale & retail | 2019 |
| NW Newfields Ltd | Real estate | 2024 |
| NW P3 Consulting Ltd | Professional & scientific | 2025 |
| Nyche Ltd | Professional & scientific | 2019 |
| O'Donnell Corporation Ltd | Health & social care | 2004 |
| O.S Warehousing Northwest Limited | Transport & logistics | 2019 |
| Oakmore Developments NW Ltd | Construction | 2024 |
| Oakview Media Ltd | Professional & scientific | 2025 |
| Oakwood Swinton Management Limited | Households | 2020 |
| Oatley Technologies Ltd. | Information & communication | 2016 |
| OB & P Dresses Ltd | Other services | 2019 |
| Obscurable Ltd | Professional & scientific | 2019 |
| Ocea Properties Ltd | Real estate | 2020 |
| Ocean Financial Investments Ltd | Financial services | 2024 |
| Oceanic (Portugal) Limited | Wholesale & retail | 2024 |
| Odontoblanc Limited | Health & social care | 2010 |
| OE2 Commercial Limited | Wholesale & retail | 2006 |
| OFF the Wall Concepts Ltd | Administrative & support | 2022 |
| Offbeat Bar Group Ltd | Hospitality | 2021 |
| OKA People and Development Limited | Professional & scientific | 2020 |
| Old LEC Ltd | Real estate | 2013 |
| Olive Tree Cocktails Limited | Wholesale & retail | 2021 |
| Olivia's Bakery Ltd | Hospitality | 2023 |
| Olympea Ltd | Manufacturing | 2025 |
| Omega Alexis Ltd | Information & communication | 2017 |
| Omega Trinity Plan Limited | Professional & scientific | 2011 |
| Omniscient Golden EYE Ltd | Real estate | 2021 |
| One Bridal Ltd | Wholesale & retail | 2025 |
| Onward Accountancy and Business Services Limited | Professional & scientific | 2017 |
| Oofm Ltd | Information & communication | 2017 |
| Oosh Performance Ltd | Wholesale & retail | 2024 |
| Opal Casa Ltd | Real estate | 2025 |
| Opal Infinity Limited | Real estate | 2015 |
| Opensource Property Ventures Ltd | Real estate | 2025 |
| Ophelia Studio Ltd | Other services | 2019 |
| Opsec Corporate Solutions Ltd | Administrative & support | 2019 |
| Opsec Group Ltd | Financial services | 2019 |
| Opsec International Solutions Ltd | Administrative & support | 2025 |
| Optimum Surface Repairs Limited | Construction | 2005 |
| Opulence Hair Ltd | Health & social care | 2018 |
| Orchard Estates (North West) Ltd | Real estate | 2018 |
| Oridan Care Limited | Health & social care | 2017 |
| Orrs Ltd | Health & social care | 2017 |
| Oscoda Solutions Ltd | Professional & scientific | 2012 |
| Osprey IT Solutions Ltd | Professional & scientific | 2009 |
| Otawell Limited | Real estate | 2002 |