| New Holmes Estate Ltd | Real estate | 2015 |
| New Home Building Construct Limited | Construction | 2025 |
| New Odyssey Education Ltd | Education | 2025 |
| New Place (Stanmore Hill) Residents Association Limited | Households | 1969 |
| New Stairlift Ltd | Manufacturing | 2024 |
| New YOU Treatments Limited | Health & social care | 2016 |
| Newarent Holdings Ltd | Real estate | 2026 |
| Newham's Yard RTM Company Limited | Households | 2026 |
| Newstone International Limited | Other services | 1996 |
| Newton AYC Holdings Ltd | Real estate | 2026 |
| Newtonsquared Limited | Administrative & support | 2014 |
| Newview Developments Limited | Real estate | 2015 |
| Nexgen Accessories Ltd | Wholesale & retail | 2019 |
| Nexora PVT Ltd | Real estate | 2024 |
| Nextgen Distribution London Limited | Wholesale & retail | 2018 |
| Nextgen Ideas Ltd | Wholesale & retail | 2020 |
| Neyava Ltd | Information & communication | 2014 |
| NGA Property Investments Limited | Real estate | 2022 |
| Ngkwansee Consultancy Limited | Professional & scientific | 2020 |
| Nhung Dang Ltd | Information & communication | 2012 |
| Nicholas Curwood Limited | Professional & scientific | 2025 |
| Nickw Associates Ltd | Professional & scientific | 2023 |
| Nicky Management Ltd | Construction | 2022 |
| Nicolae Building Ltd | Construction | 2022 |
| Niduwara Ltd | Transport & logistics | 2025 |
| Nightingale Court (Radlett) Freehold Ltd | Households | 2026 |
| Nightingale Court Management Company (Radlett) Limited | Households | 2003 |
| Niharti Limited | Extraterritorial | 2017 |
| Niks Global Limited | Wholesale & retail | 2017 |
| Nile Investments Ltd | Real estate | 2017 |
| Nilesh Mayani Electrical Solutions Limited | Construction | 2016 |
| Nilsum Ltd | Real estate | 2003 |
| Nimara Holdings Ltd | Financial services | 2025 |
| Nimbs Ltd | Wholesale & retail | 2024 |
| Nimpex Investments Limited | Real estate | 2017 |
| Nine Lloyd House Limited | Arts & recreation | 2017 |
| Nine Property Limited | Real estate | 2017 |
| Nine Rivers Property Investment Ltd | Real estate | 2025 |
| Nineteen Fifteen Productions Ltd | Information & communication | 2009 |
| Nineup AI Ltd | Information & communication | 2026 |
| Nipra Limited | Wholesale & retail | 2014 |
| Nirka Limited | Information & communication | 2025 |
| Nirmal Limited | Health & social care | 2015 |
| Nirmatru Limited | Information & communication | 2020 |
| Nirmiti Limited | Information & communication | 2022 |
| Nirvair Consulting Limited | Professional & scientific | 2022 |
| Nirvana Pillar Ltd | Real estate | 2019 |
| Nirvana Ventures Group Limited | Construction | 2024 |
| Nisacraftcare Limited | Health & social care | 2018 |
| Nitrya Ltd | Information & communication | 2025 |
| Nits Solutions Limited | Information & communication | 2014 |
| Niva Medical Clinic Ltd | Health & social care | 2024 |
| Nivesha Limited | Real estate | 2024 |
| NJS Digital Ltd | Information & communication | 2015 |
| NK Medics Ltd | Other services | 2016 |
| NKN Optics Ltd | Health & social care | 2024 |
| NO Bars Ltd | Professional & scientific | 2025 |
| NO Hiding Place Limited | Administrative & support | 2024 |
| NO.19 Projects Limited | Construction | 2018 |
| NO1MSP Ltd. | Construction | 2016 |
| Noally Limited | Wholesale & retail | 2012 |
| Noble Guard Defense Ltd | Financial services | 2026 |
| Noble Horse Properties Limited | Real estate | 2013 |
| Noble Trading and Investments Limited | Professional & scientific | 2016 |
| Nobletest Services Ltd | Wholesale & retail | 2018 |
| Nobody Builders Limited | Construction | 2008 |
| Nogood Boyo Limited | Arts & recreation | 2025 |
| Noli Fitness Ltd | Arts & recreation | 2026 |
| Noor (NWL) Limited | Real estate | 2011 |
| Noor Foods Station Limited | Hospitality | 2019 |
| Nordiccloud Consulting Limited | Information & communication | 2019 |
| Nordmann GmbH Limited | Wholesale & retail | 2023 |
| Norfolk Premier Properties Ltd | Real estate | 2012 |
| North and Broadway Ltd | Real estate | 2011 |
| North London Autos Ltd | Wholesale & retail | 2026 |
| North London Psychologists Ltd | Health & social care | 2018 |
| North West London Birds Ltd | Wholesale & retail | 2024 |
| Northbridge Ltd | Information & communication | 2025 |
| Northfield Financial Services Limited | Administrative & support | 1995 |
| Northfields Lettings Limited | Real estate | 2019 |
| Northmere Terra Limited | Real estate | 2026 |
| Northport Waltham Cross Limited | Real estate | 2019 |
| Norwich House (Streatham) RTM Company Limited | Households | 2020 |
| Norwood Ravenswood | Education | 1996 |
| Norwood Ravenswood Services Ltd | Health & social care | 1988 |
| Norwood Schools Ltd. | Health & social care | 1953 |
| Noticevale Limited | Arts & recreation | 1982 |
| Nottii Limited | Other services | 2012 |
| Nouvelle Delicatessen Limited | Hospitality | 2016 |
| Nova Building RTM Company Ltd | Households | 2011 |
| Nova Resources Limited | Wholesale & retail | 1998 |
| Novagl Construct Ltd | Construction | 2025 |
| Novastix Global Ltd | Wholesale & retail | 2026 |
| Noviscope Limited | Real estate | 2011 |
| Novodel Logistics Limited | Transport & logistics | 2021 |
| Novus Components Limited | Wholesale & retail | 2026 |
| Nowshin & Nishad Limited | Wholesale & retail | 2016 |
| Noyo Food Limited | Other services | 2014 |
| NP Build Ltd | Construction | 2026 |
| NP3 Limited | Real estate | 2019 |