| Nawaie Motoring Ltd | Wholesale & retail | 2012 |
| Nayee & Sons Limited | Wholesale & retail | 2014 |
| NDC Construction Limited | Other services | 2018 |
| Neal Sourcing Ltd | Wholesale & retail | 2026 |
| NEB Services Ltd | Professional & scientific | 2024 |
| Nebel Limited | Wholesale & retail | 2022 |
| Necessity Supplies Limited | Wholesale & retail | 1986 |
| Neel Radia Limited | Hospitality | 2011 |
| Neemiah Expert Home Renovation Ltd | Construction | 2025 |
| Neet London Ltd | Wholesale & retail | 2018 |
| Negan Planning Limited | Professional & scientific | 2016 |
| Nehaa Fast Food Ltd | Hospitality | 2020 |
| Nehaa Properties Ltd | Real estate | 2026 |
| Neil Netto Limited | Professional & scientific | 1997 |
| Nemat Tech Limited | Wholesale & retail | 2017 |
| Nemm Foods Ltd | Wholesale & retail | 2018 |
| Nepalrun ORG Ltd | Arts & recreation | 2018 |
| Netto & Company Limited | Professional & scientific | 1996 |
| Nevan KIT Ltd | Other services | 2024 |
| Never Ending Christmas Ltd | Wholesale & retail | 2022 |
| Nevil Engineering Limited | Professional & scientific | 2024 |
| New Nana Foods Ltd | Wholesale & retail | 2018 |
| New Sun Builders Ltd | Construction | 2016 |
| New Talha Gold Smith UK Ltd | Other services | 2006 |
| New Tasty House Ltd | Hospitality | 2021 |
| Newbury Way Freehold Limited | Real estate | 2009 |
| Newcomers to London and the South East Limited | Hospitality | 1991 |
| Nexa Security Services Limited | Administrative & support | 2024 |
| Next Level Construction Ltd | Construction | 2019 |
| Nice Construction Ltd | Construction | 2017 |
| Nicholas Guard Security Ltd | Administrative & support | 2026 |
| NIK HO Limited | Other services | 2025 |
| Nik's Grooming Ltd | Other services | 2020 |
| Nikos Ghera Ltd | Construction | 2020 |
| Niksan Services Limited | Administrative & support | 2018 |
| Nimbusweb Ltd | Information & communication | 2004 |
| Nimbusweb Support Ltd | Information & communication | 2011 |
| Nine Rivers Limited | Health & social care | 2012 |
| NINE215 Ltd | Administrative & support | 2025 |
| Niral Medical Limited | Health & social care | 2009 |
| Nirmal Niwas Ltd | Real estate | 2024 |
| Nirvamo Limited | Administrative & support | 2024 |
| Nisa Corner Ltd | Wholesale & retail | 2023 |
| Nismo Motors Ltd | Wholesale & retail | 2022 |
| Nisvek Developer Limited | Construction | 2025 |
| Nive & Suve UK Limited | Other services | 2025 |
| Nivora Pure Ltd | Manufacturing | 2025 |
| NK & Sons Ltd | Wholesale & retail | 2024 |
| NK Cleaning Services Ltd | Administrative & support | 2017 |
| NK Surveys Limited | Professional & scientific | 2015 |
| NMD Consultants Ltd | Real estate | 2020 |
| NMT Builders Limited | Construction | 2019 |
| NO Broker Ltd | Wholesale & retail | 2025 |
| NO One Really Cares Ltd | Information & communication | 2023 |
| Noirjwls Ltd | Wholesale & retail | 2024 |
| Noor Constructions Ltd | Construction | 2014 |
| Noor Household Essentials Ltd | Wholesale & retail | 2023 |
| Noordin Investments Limited | Real estate | 2014 |
| Nordic HEM Assets Limited | Real estate | 2025 |
| North END Food & Wine Limited | Wholesale & retail | 2024 |
| North END Road PO Ltd | Transport & logistics | 2025 |
| Northala Health Care Limited | Health & social care | 2021 |
| Northampton Property Limited | Real estate | 2018 |
| Northland Holdings Group Limited | Real estate | 2022 |
| Northolt Computers Ltd | Information & communication | 2024 |
| Northolt Investment Ltd | Real estate | 2014 |
| Northolt Laundrette Ltd | Other services | 2014 |
| Northolt Ricestylers Ltd | Hospitality | 2025 |
| Northolt Tyres Ltd | Wholesale & retail | 2025 |
| Notting Hill Drycleaners Ltd | Other services | 2026 |
| Nova Landscapes Ltd | Wholesale & retail | 2024 |
| Novaride Motorcycles Ltd | Wholesale & retail | 2026 |
| NOY Brothers Enterprises Ltd | Wholesale & retail | 2017 |
| NSL (Holdings) Limited | Wholesale & retail | 2014 |
| NSL Group Limited | Wholesale & retail | 2008 |
| Nstv Ltd | Construction | 2023 |
| Nsubugawholesale Ltd | Wholesale & retail | 2025 |
| NTJ Services Ltd | Transport & logistics | 2025 |
| Nutcracker Research Limited | Professional & scientific | 2013 |
| NW Property Developers Ltd | Real estate | 2024 |
| Nxetstep Ltd | Other services | 2024 |
| O & a Building Services Limited | Construction | 2003 |
| O'Neal Building Contractors Limited | Construction | 2016 |
| O'Neill Building Services Ltd | Construction | 2011 |
| O.P.C Optik Polish Car Ltd | Administrative & support | 2026 |
| Oak Childcare Services Ltd | Health & social care | 2024 |
| Oak Healthcare Services Limited | Administrative & support | 2025 |
| Oak Software Testing Ltd | Extraterritorial | 2020 |
| Oakvein Ltd | Construction | 2019 |
| OCD Sprays UK Ltd | Construction | 2023 |
| Ocean Bite Group Ltd | Hospitality | 2026 |
| Ocean Tower Ltd | Administrative & support | 2012 |
| Octavian Estates Limited | Real estate | 2023 |
| Octavion Retail Limited | Wholesale & retail | 2026 |
| OFF Label Limited | Manufacturing | 2024 |
| Offquid Ltd | Information & communication | 2026 |
| OJ Ecommerce Ltd | Manufacturing | 2025 |
| Oknoglass Limited | Construction | 2010 |
| OKZ Fitness Ltd | Arts & recreation | 2026 |
| Old Stratford Village Store Ltd | Wholesale & retail | 2015 |