| Myskin Ltd | Health & social care | 2025 |
| N & M Homes Ltd | Real estate | 2021 |
| N Baker Ltd | Administrative & support | 2018 |
| N R Capital Estates Limited | Real estate | 2018 |
| N R Real Estate Limited | Real estate | 2011 |
| N Walker Contract Management Ltd | Construction | 2022 |
| N-Phonic Limited | Information & communication | 2024 |
| N-Tec Consulting Limited | Information & communication | 2013 |
| N.B. Photos Limited | Professional & scientific | 2010 |
| N.J. Cooper Limited | Real estate | 2022 |
| N8R9PROPERTY Ltd | Real estate | 2025 |
| Nadamy Consulting Limited | Information & communication | 2007 |
| Nana Fanny's Limited | Wholesale & retail | 2013 |
| Nanolabrx Limited | Administrative & support | 2022 |
| Nardi Properties Ltd | Real estate | 2022 |
| NAS Pro Building Services Ltd | Construction | 2023 |
| Nascot Watford Limited | Hospitality | 2023 |
| Naseby Commodities Ltd | Financial services | 2014 |
| National Rivers Consortium Limited | Construction | 2024 |
| Nato Construction Limited | Construction | 2021 |
| Naval ROW Residents Association Limited | Households | 2000 |
| NB Electrical Solutions Limited | Construction | 2015 |
| NCG Golf Ltd | Wholesale & retail | 2026 |
| NCH Holdings Limited | Real estate | 2026 |
| Ncmedispa Ltd | Other services | 2024 |
| NCQ Developments Limited | Administrative & support | 2016 |
| Neatis Limited | Construction | 2016 |
| Nedluob Limited | Financial services | 2021 |
| Nehira Limited | Hospitality | 2025 |
| Neil French Property Limited | Real estate | 2023 |
| Neos Logistics LLP | | 2005 |
| Neptune Arch Limited | Administrative & support | 2024 |
| Neptune BTR Limited | Administrative & support | 2024 |
| Neptune Operations Limited | Administrative & support | 2024 |
| Nerdab Ltd | Health & social care | 2023 |
| NET Nexus Global Ltd | Information & communication | 2024 |
| Netcircle Limited | Administrative & support | 2003 |
| Netlink Limited | Construction | 2003 |
| Network Infrastructure Ltd | Construction | 2024 |
| Networkx Technology Limited | Information & communication | 2018 |
| Neuemark Ltd | Professional & scientific | 2019 |
| Neutral Axis Ltd | Construction | 2025 |
| Never Fully Dressed Limited | Wholesale & retail | 2010 |
| New Addington Estates Ltd | Real estate | 2024 |
| New Breed Bottle Shop Ltd | Wholesale & retail | 2020 |
| New Build Snagging Specialists Ltd | Professional & scientific | 2021 |
| New Concept Furnishings Limited | Administrative & support | 2014 |
| New Country Homes Limited | Construction | 1999 |
| New Life Worship Centre Limited | Other services | 2013 |
| New London Kitchens Ltd | Construction | 2019 |
| New Loughton Food&Wine Ltd | Wholesale & retail | 2020 |
| New Mayfair Estates Limited | Real estate | 2017 |
| New Road Residents Company Limited | Households | 1978 |
| New Things Digital Limited | Professional & scientific | 2020 |
| Newbuildsnaggingprofessionals Ltd | Construction | 2024 |
| Newdawn Horizons Ltd | Real estate | 2021 |
| Neweastcote Ltd | Construction | 2023 |
| Newham Chamber of Commerce Limited | Administrative & support | 1984 |
| Newman Project Consultants Limited | Professional & scientific | 2007 |
| Newpulse Limited | Construction | 2003 |
| Newstyles London Ltd | Wholesale & retail | 2024 |
| Newton & Newton Investments Limited | Real estate | 2024 |
| Next Steps Executive Search Ltd | Professional & scientific | 2019 |
| Nextegen Softworks Ltd | Administrative & support | 2025 |
| Nextgen Property Investment Ltd | Construction | 2023 |
| NFG Wellbeing Limited | Professional & scientific | 2017 |
| NGM Consulting Limited | Information & communication | 2024 |
| NGN Investment & Property Ltd | Real estate | 2026 |
| NHA Trang Kitchen Ltd | Hospitality | 2015 |
| NHI Consulting Group Ltd | Information & communication | 2025 |
| NHI Training Group Ltd | Education | 2025 |
| Nhim Group Ltd | Information & communication | 2024 |
| NHT Capital Limited | Financial services | 2026 |
| Nichols Interiors & Construction Limited | Construction | 2002 |
| Nicholson Property Limited | Extraterritorial | 2016 |
| Nicholsons Properties Limited | Real estate | 2016 |
| NICK88 Carpentry Ltd | Construction | 2020 |
| Nicky Picky Limited | Wholesale & retail | 2025 |
| Nidus Living Limited | Real estate | 2026 |
| Nigel Catmur Lighting Design Limited | Professional & scientific | 2011 |
| Nigeladams&Co Limited | Real estate | 2016 |
| Nightingale Court (Freehold) Limited | Real estate | 2010 |
| Nightingale Rise Residents Company Limited | Households | 1998 |
| Nightingill Management Limited | Professional & scientific | 2007 |
| Nightingill Property Investments Limited | Financial services | 2013 |
| NIH (UK) Limited | Construction | 2012 |
| NIKO99 Ltd | Construction | 2019 |
| Nilasri Consulting & Advisory Ltd | Information & communication | 2026 |
| Nilgara Holdings Ltd | Financial services | 2020 |
| Nine the Label Ltd | Wholesale & retail | 2021 |
| Ninetyfour Labs Ltd | Wholesale & retail | 2025 |
| Nitram Online Ltd | Information & communication | 2025 |
| Nixon Security Services Limited | Administrative & support | 2020 |
| NKT Interiors Ltd | Construction | 2017 |
| NKT Logistics Ltd | Transport & logistics | 2021 |
| NLT Garden Supplies Limited | Wholesale & retail | 2020 |
| NMS Management Limited | Professional & scientific | 2016 |
| NO Limitz Ltd | Wholesale & retail | 2025 |
| NO. 6 the Avenue Management Company Limited | Households | 2006 |
| NO1 Meal Prep Ltd | Administrative & support | 2018 |