| Niche Data Ltd | Information & communication | 2018 |
| Niche Land Promotions Ltd | Construction | 2016 |
| Nicholas Anthony Holdings Limited | Financial services | 2023 |
| Nick Herbert Consulting Ltd | Professional & scientific | 2021 |
| Nick Johnson Solutions Ltd | Information & communication | 2013 |
| Nicki Chennells Associates Ltd | Professional & scientific | 2020 |
| Nicofruit Associates Limited | Wholesale & retail | 2023 |
| Nicola E Giovanni Limited | Hospitality | 2018 |
| Nicole&Nicolas Logistics and Transport Ltd | Transport & logistics | 2024 |
| Nicoleta Limited | Hospitality | 2017 |
| Nidima Ltd | Real estate | 2021 |
| Nigel Musto Limited | Professional & scientific | 2015 |
| Nigel Toseland Consultancy Ltd | Professional & scientific | 2010 |
| Night Sky Dreams Ltd | Administrative & support | 2019 |
| Night TIL Dawn Ltd | Manufacturing | 2023 |
| Nihcasb Limited | Professional & scientific | 2025 |
| NIM Property Limited | Construction | 2025 |
| Nimbos Communications Limited | Information & communication | 2010 |
| Nimers Limited | Administrative & support | 2022 |
| Nimiskitchen Ltd | Hospitality | 2024 |
| Nimrod Properties Limited | Real estate | 2021 |
| Nine Lives Enterprises Limited | Information & communication | 2010 |
| Ninja Business Ltd | Professional & scientific | 2025 |
| Ninja Printing UK Limited | Manufacturing | 2020 |
| Ninox Technology Limited | Manufacturing | 2012 |
| Ninth Seat Group Limited | Administrative & support | 2015 |
| Ninth Seat Limited | Professional & scientific | 1985 |
| Nipsha Nexus Ltd | Education | 2026 |
| Nirvana Chartering Ltd | Administrative & support | 2025 |
| Nispet Bar & Restaurant Ltd | Hospitality | 2019 |
| Nivalo Care Services Limited | Health & social care | 2020 |
| Nivasa Properties Limited | Real estate | 2025 |
| NJ Drafting Ltd | Professional & scientific | 2023 |
| Njiw Limited | Manufacturing | 2019 |
| NKD Maritime Limited | Wholesale & retail | 2003 |
| NKG PVT Limited | Wholesale & retail | 2019 |
| NKN Estates Ltd | Real estate | 2017 |
| NKN Limited | Health & social care | 2010 |
| Nlbe Ltd | Construction | 2014 |
| NLC Chelmsford Limited | Real estate | 2021 |
| NLC Management Company (Chelmsford) Ltd | Households | 2026 |
| NLS Compliance Solutions Ltd | Administrative & support | 2025 |
| NM Meijer Consulting Ltd | Professional & scientific | 2019 |
| NMF Consulting Services Limited | Professional & scientific | 2022 |
| NMI UK Group Ltd | Wholesale & retail | 2019 |
| NMS Technology Solutions Ltd | Information & communication | 2024 |
| Nmtransformation Ltd | Other services | 2025 |
| NN Urban Ltd | Wholesale & retail | 2026 |
| NO 6 Clothing Limited | Wholesale & retail | 2014 |
| NO Small Business Ltd | Real estate | 2025 |
| NO.1 FAN Ltd | Education | 2022 |
| Noak Management Services Limited | Professional & scientific | 2008 |
| Noble Abode Ltd | Real estate | 2020 |
| Noble Towers Ltd | Real estate | 2021 |
| Noblehands Care Recruitment Limited | Administrative & support | 2026 |
| Nobster Property Management Limited | Real estate | 2022 |
| Nodders Ltd | Wholesale & retail | 2025 |
| Nodemax Limited | Information & communication | 2007 |
| Noel Sawyer CBT Services Ltd | Professional & scientific | 2014 |
| Nokomis Health Europe Limited | Information & communication | 2019 |
| Nomad Arts Group Ltd | Wholesale & retail | 2022 |
| Nomad Global UK Partnership Ltd | Arts & recreation | 2025 |
| Nomadsync Ltd | Information & communication | 2025 |
| Noodles Chelmsford Ltd | Hospitality | 2023 |
| Nook Service Station Limited | Extraterritorial | 2017 |
| Noor Data Solutions Ltd | Professional & scientific | 2018 |
| Noown Limited | Extraterritorial | 2024 |
| NOR Management Consultancy Limited | Construction | 2013 |
| Norbury Consulting Ltd | Professional & scientific | 2016 |
| Norcom Access Limited | Administrative & support | 2004 |
| Norman Garon Trust | Arts & recreation | 2007 |
| Norms Care Services Ltd | Public administration | 2025 |
| Norrington Retail Limited | Financial services | 2023 |
| Norrscope Limited | Other services | 2016 |
| North 36 Ltd | Other services | 2019 |
| North Avenue Development Co (Two) Ltd | Construction | 2020 |
| North Avenue Development Co Ltd | Construction | 2011 |
| North Circle Coaching Limited | Professional & scientific | 2026 |
| North Highland Solutions Ltd | Wholesale & retail | 2017 |
| North Sea Maritime Limited | Professional & scientific | 2009 |
| North Sea Maritime Yacht Sales Limited | Wholesale & retail | 2009 |
| North Street Carpet and Beds Limited | Other services | 2002 |
| Northfleet Property 1 Limited | Real estate | 2019 |
| Northfleet Property 2 Limited | Real estate | 2019 |
| Northfleet Property LLP | | 2015 |
| Northgate Industrial Park Limited | Construction | 2016 |
| Northoaks Capital Ltd | Administrative & support | 2023 |
| Northwood Chelmsford Limited | Real estate | 2004 |
| Northwood Essex Financial Ltd | Financial services | 2025 |
| Norton Court Developments Ltd | Construction | 2024 |
| Norton Medical Services Limited | Health & social care | 2019 |
| Norwich Fireplaces and Woodburners Limited | Wholesale & retail | 2015 |
| Norwood & Hawes Ltd | Wholesale & retail | 2023 |
| Nostalgia TCG Limited | Wholesale & retail | 2022 |
| NOT on the NET Ltd | Financial services | 2023 |
| Notley Tanning Limited | Other services | 2002 |
| Noto Consultancy Ltd | Construction | 2020 |
| Nourished Inspirations CIC | Health & social care | 2023 |
| Nova SM Limited | Wholesale & retail | 2024 |
| Nova Zeal Limited | Wholesale & retail | 2024 |