| Nine Reading Hotel Limited | Hospitality | 2016 |
| Nine Two Holdings Ltd | Professional & scientific | 2023 |
| Nine Ventures Limited | Real estate | 2014 |
| Nine Wicker Management Limited | Real estate | 2013 |
| NINE6THREE Services Ltd | Information & communication | 2021 |
| NIP Construction Ltd | Construction | 2019 |
| Nipco Limited | Information & communication | 2012 |
| Nirma Cleaning Ltd | Administrative & support | 2026 |
| Niru Business Consultant Ltd | Information & communication | 2023 |
| Nirvana Brands Holdings Ltd | Financial services | 2021 |
| Nirvana Brands Ltd | Wholesale & retail | 2019 |
| Nirvana Brands Worldwide Ltd | Administrative & support | 2021 |
| Nirvi Aura Ltd | Wholesale & retail | 2025 |
| NIS Plumbing Limited | Construction | 2023 |
| Nisaar Ltd | Hospitality | 2025 |
| Nisai Education Trust Limited | Education | 2013 |
| Nisai Group Limited | Information & communication | 1996 |
| Nisai Learning Limited | Education | 2015 |
| Nisai Skills Academy Limited | Information & communication | 2003 |
| Nisai Virtual Academy Limited | Education | 2004 |
| Nish Dimensional Limited | Education | 2019 |
| Nishtha Ltd | Wholesale & retail | 2022 |
| Nisk Consultancy Ltd | Professional & scientific | 2025 |
| Nislux Property Ltd | Real estate | 2026 |
| Nita Pankhania Ltd | Education | 2021 |
| Nivara Ltd | Wholesale & retail | 2025 |
| Nivasa Management Ltd | Real estate | 2014 |
| Nixie Consultancy Ltd | Information & communication | 2018 |
| Nixon Interiors Ltd | Administrative & support | 2015 |
| Niyman Estate Ltd | Real estate | 2025 |
| Niyman Limited | Information & communication | 2025 |
| Niyo Pharma Services Limited | Information & communication | 2022 |
| NJ & Sons Constructions Ltd | Construction | 2024 |
| NJ Design Services Limited | Professional & scientific | 2008 |
| NJ Trading London Limited | Wholesale & retail | 2025 |
| NJB Consultings 99 Limited | Financial services | 2024 |
| Njbrown Holdings Ltd | Financial services | 2024 |
| Njgraphique Ltd | Professional & scientific | 2017 |
| NJK Finance Services Limited | Professional & scientific | 2021 |
| NJM Film Ltd | Professional & scientific | 2026 |
| Njnl Properties Limited | Real estate | 2018 |
| NJP Solutions Limited | Real estate | 2014 |
| NJR Developments Limited | Real estate | 2016 |
| NJS Communications Limited | Administrative & support | 2015 |
| NJT Consulting Limited | Information & communication | 2013 |
| NK Property Services Ltd | Construction | 2018 |
| NK Vora Limited | Financial services | 2019 |
| NKA Balance Books Ltd | Professional & scientific | 2024 |
| Nkcc Ltd | Administrative & support | 2013 |
| Nksk Limited | Professional & scientific | 2025 |
| NL Enhance Beauty Ltd | Other services | 2023 |
| NLC Properties LLP | | 2003 |
| Nlighten Agile Services Limited | Education | 2013 |
| NLP School Limited | Administrative & support | 2005 |
| NM Delta Limited | Information & communication | 2014 |
| NMA Tools Ltd | Wholesale & retail | 2025 |
| Nmaoha Global Ltd | Real estate | 2024 |
| NMC Consultancy (UK) Limited | Professional & scientific | 2014 |
| Nmcb Consulting Limited | Professional & scientific | 2010 |
| NNA Consultants Limited | Professional & scientific | 2024 |
| Nnaco Limited | Health & social care | 2021 |
| NNC Supported Living Ltd | Health & social care | 2023 |
| Nndev Properties Ltd | Financial services | 2022 |
| Nnks Ltd | Professional & scientific | 2021 |
| NO 1 at Downing Street Limited | Arts & recreation | 2020 |
| NO Give UP Ltd | Wholesale & retail | 2025 |
| NO. 1 London Holdings Limited | Financial services | 2026 |
| NO. 14 Steeles Road Management Company Limited | Real estate | 1979 |
| NO. 40 Bassett Road Limited | Extraterritorial | 1982 |
| NO10DOWNINTHESTREET Limited | Arts & recreation | 2020 |
| NO203 Ltd | Hospitality | 2025 |
| NOA Group Ltd | Wholesale & retail | 2018 |
| NOA Services Limited | Information & communication | 2018 |
| Nobilitas Consulting Limited | Information & communication | 2016 |
| Noble House Moving Ltd | Transport & logistics | 2025 |
| Noblecase Limited | Real estate | 1997 |
| Noblefield Heights Residents Association Limited | Real estate | 1991 |
| Nobu Autocare Ltd | Wholesale & retail | 2021 |
| Nocturne Events Ltd | Arts & recreation | 2026 |
| Nodn Ltd | Administrative & support | 2023 |
| Nogah Limited | Administrative & support | 2017 |
| Nolan Project Services Ltd | Professional & scientific | 2014 |
| Nolla Carbon Limited | Manufacturing | 2026 |
| Nomad Hotel Manager London Limited | Hospitality | 2017 |
| Nomimono Limited | Hospitality | 2026 |
| Nomusa-Liv Limited | Health & social care | 2024 |
| Nonagon Consultancy Ltd | Professional & scientific | 2021 |
| None the Wiser Ltd | Information & communication | 2023 |
| Nonsuch Finance Limited | Professional & scientific | 2024 |
| Nook and Niche Limited | Other services | 2021 |
| Nookstone Limited | Real estate | 2025 |
| Noone Construction Services Limited | Construction | 2018 |
| Noorig Ltd | Professional & scientific | 2021 |
| Nora Homes Limited | Real estate | 2026 |
| Nora RAE Ltd | Hospitality | 2025 |
| Norcloud Ltd | Information & communication | 2017 |
| Nordic Brand Studio Limited | Wholesale & retail | 2023 |
| Nordpay Financial Limited | Information & communication | 2010 |
| Norland Equity Partners Acquisition Limited | Financial services | 2023 |
| Normandia Ltd | Wholesale & retail | 2025 |