| Moxie Academy Limited | Arts & recreation | 2021 |
| Mpaulapop Limited | Other services | 2024 |
| MR Chips (UK) LLP | | 2014 |
| MSF Property Investment Limited | Real estate | 2024 |
| MSM Productions Limited | Arts & recreation | 2016 |
| MUGALU123 Limited | Health & social care | 2019 |
| Mungo Productions Limited | Information & communication | 2015 |
| Music and Management.Com Limited | Professional & scientific | 2002 |
| MWC (Newquay) Ltd | Administrative & support | 2021 |
| My Atmosphere Limited | Information & communication | 2020 |
| My Digital DEV Ltd | Administrative & support | 2016 |
| My Nuhome Ltd | Real estate | 2019 |
| My Retail Solutions Ltd | Wholesale & retail | 2021 |
| My Wine Time Limited | Wholesale & retail | 2018 |
| Myclassroom Ltd | Education | 2023 |
| Myergo Limited | Wholesale & retail | 2019 |
| Mykey AV Limited | Professional & scientific | 2024 |
| Mylosystem Limited | Manufacturing | 1997 |
| Naazcare UK Ltd | Professional & scientific | 2018 |
| Nachure Ltd | Health & social care | 2015 |
| Naeto Koby Ltd | Health & social care | 2022 |
| Nafees Food Limited | Wholesale & retail | 2020 |
| Nakof Company Ltd | Health & social care | 2019 |
| Namacare Service Providers Ltd | Health & social care | 2020 |
| Nannyme Limited | Health & social care | 2024 |
| Natasha Alexandra Limited | Administrative & support | 2012 |
| Nathan Hassall Music Ltd | Arts & recreation | 2013 |
| Natmax Ltd | Wholesale & retail | 2019 |
| Nature's Brickwork & Landscaping Ltd | Construction | 2024 |
| Nazia Memon Ltd | Wholesale & retail | 2020 |
| NCJ Distributors Limited | Transport & logistics | 2006 |
| Neaa Group Limited | Real estate | 2025 |
| Neat Chances Limited | Education | 2026 |
| Neem Tree Events Ltd | Arts & recreation | 2023 |
| Neeson Enterprise Ltd | Health & social care | 2018 |
| Neevari Ltd | Real estate | 2024 |
| Neil Chotai Orthopaedics Ltd | Health & social care | 2025 |
| Neil Fisher Developments Limited | Real estate | 2018 |
| Neil Turner Associates Limited | Professional & scientific | 2005 |
| Nemuch Tech Ltd | Construction | 2015 |
| Neomars Limited | Wholesale & retail | 2016 |
| Neoworks Ltd | Professional & scientific | 2014 |
| Netherne Green Limited | Households | 2011 |
| Netherne Green Management Company Limited | Households | 2002 |
| Networks Investment Ltd | Real estate | 2019 |
| Neurovascular Therapeutics Ltd | Health & social care | 2025 |
| Nevaeh Consultations Ltd | Professional & scientific | 2025 |
| Nevaeh Investments Ltd | Real estate | 2022 |
| New ERA Property Services Ltd | Construction | 2019 |
| Next Unicorn Innovations Ltd | Information & communication | 2024 |
| Niche Property Consultancy Limited | Real estate | 2011 |
| Niche Property Development Limited | Real estate | 2011 |
| Niche Property Finance Limited | Financial services | 2020 |
| Niche Property Limited | Real estate | 2016 |
| Niche Records Limited | Extraterritorial | 2016 |
| Nicholson Malnoe Ltd | Other services | 2024 |
| Nick Thacker Consultancy Ltd | Information & communication | 2018 |
| Nimax Holdings Limited | Professional & scientific | 2000 |
| Nineteen Developments Limited | Real estate | 2018 |
| Ninox Limited | Professional & scientific | 2021 |
| NJ Management Services Limited | Professional & scientific | 2020 |
| NJC Audio Products Ltd | Wholesale & retail | 2018 |
| NJC Ventures Limited | Information & communication | 2011 |
| NJJ Health Ltd | Health & social care | 2023 |
| NM and Partners Limited | Real estate | 2021 |
| NNB Consultancy Ltd | Professional & scientific | 2024 |
| NNB Service Ltd | Construction | 2024 |
| NO.77 Ltd | Other services | 2022 |
| Noke Farm Barns Residents Company Limited | Households | 2002 |
| Noorz Wood Pizzeria Limited | Hospitality | 2018 |
| Nordlife Ltd. | Wholesale & retail | 2019 |
| North of Purley Limited | Real estate | 2018 |
| Northern Dynamics Ltd | Information & communication | 2023 |
| Northern Recruitment Group Limited | Administrative & support | 1983 |
| Noteable Ltd | Construction | 2025 |
| Novex Advisory Limited | Real estate | 2025 |
| NOW There's (Quote): 'NO Saleability Here' Ever Hahaha!!! Ltd | Professional & scientific | 2019 |
| NQ Assets Ltd | Real estate | 2025 |
| NRB Property Ltd | Real estate | 2016 |
| Nsrd Properties Ltd | Real estate | 2025 |
| NT Security Systems Limited | Professional & scientific | 2013 |
| Number 34 Limited | Professional & scientific | 2024 |
| Numeryka Ltd | Professional & scientific | 2012 |
| Nureyi Consulting Ltd | Information & communication | 2022 |
| Nursdoc Limited | Administrative & support | 2013 |
| Nursing Direct Healthcare Limited | Health & social care | 2016 |
| Nusa Investments Ltd | Construction | 2021 |
| NVT Real Estate Ltd | Real estate | 2025 |
| NY Assets Ltd | Real estate | 2024 |
| NY Group Holdings Ltd | Financial services | 2024 |
| NY Group London Ltd | Construction | 2025 |
| Nyero Ltd | Professional & scientific | 2020 |
| NYQ Assets Ltd | Real estate | 2025 |
| Oak and ASH Furniture Ltd | Wholesale & retail | 2026 |
| Oak and Horizon Property Investment Ltd | Real estate | 2025 |
| Oak and ROW Estates Ltd | Real estate | 2025 |
| Oakwood Septimus Limited | Real estate | 2018 |
| Obamedo Consulting Limited | Information & communication | 2015 |
| Odek Techcraft Ltd | Financial services | 2003 |
| Officium Building Management Systems Limited | Construction | 2017 |