| Mushi Mushi Limited | Agriculture & fishing | 2026 |
| Music for Television Limited | Information & communication | 1997 |
| Music Gate Limited | Construction | 2018 |
| Music Makers Business Development Consulting Limited | Administrative & support | 2004 |
| Musigooroo Limited | Arts & recreation | 2017 |
| Musiime Estates Limited | Real estate | 2020 |
| Mvci Ltd | Professional & scientific | 2013 |
| MW Coffee Ltd | Hospitality | 2018 |
| Mwangi Automotive Services Ltd | Professional & scientific | 2014 |
| Mweb Media Ltd | Information & communication | 2015 |
| Mwhp Consulting Limited | Professional & scientific | 2015 |
| Mwitasame Holdings Ltd | Financial services | 2024 |
| MXP Media Ltd | Information & communication | 2026 |
| My 1ST Photos Ltd | Wholesale & retail | 2017 |
| My Accounts Dept Limited | Professional & scientific | 2016 |
| My Digi Coach Ltd | Information & communication | 2025 |
| My Little Pickle & Co. Ltd | Manufacturing | 2022 |
| My Local Enterprise Group Limited | Administrative & support | 2017 |
| My Lovely Drives & Patios Limited | Administrative & support | 2023 |
| Myaxis Limited | Information & communication | 2010 |
| Mybreaktrip Limited | Administrative & support | 2011 |
| Mycelium Interactive Ltd | Professional & scientific | 2023 |
| Myeneed Ltd | Wholesale & retail | 2025 |
| Myrn Silk Ltd | Wholesale & retail | 2025 |
| Mystique Yachts Limited | Transport & logistics | 2024 |
| Mytradepay Limited | Financial services | 2019 |
| N & G Gardening Surrey Ltd | Administrative & support | 2026 |
| N & N Consulting Limited | Information & communication | 2016 |
| N & R Kumar Limited | Health & social care | 2025 |
| N a Samels Catering Limited | Hospitality | 2008 |
| N&B Property Limited | Real estate | 2023 |
| N1 Pharmaceutical Partners Limited | Manufacturing | 2025 |
| N4VNK Limited | Health & social care | 2014 |
| Naakaa Ltd | Hospitality | 2024 |
| Naali Limited | Other services | 2024 |
| NAB Plumbing and Heating Limited | Construction | 2014 |
| Nahdatul Ummah CIC | Education | 2026 |
| Nahid Residential Limited | Hospitality | 2014 |
| Naked EYE Limited | Professional & scientific | 2004 |
| Namecamp Limited | Information & communication | 2013 |
| Namescape Limited | Arts & recreation | 2015 |
| Nanagon Limited | Professional & scientific | 2017 |
| Nankai Poling UK Ltd | Education | 2012 |
| Nanny Mchaffee Childcare Limited | Other services | 2016 |
| Nanolayr UK Limited | Manufacturing | 2019 |
| Nanson House Ltd | Real estate | 2016 |
| Nanyang Brothers Tobacco Company Limited | Professional & scientific | 1990 |
| Naomi Wilson Clinical Psychology Limited | Other services | 2017 |
| Nash Estate Homes Limited | Real estate | 2026 |
| Nashville Investments | Administrative & support | 2025 |
| Natalie Jane Enterprises Ltd | Administrative & support | 2019 |
| Nathan Enterprize Ltd | Professional & scientific | 2015 |
| National Heathland Conference CIC | Administrative & support | 2024 |
| National Three Peaks Challenge Ltd | Extraterritorial | 2021 |
| National Three Peaks Ltd | Extraterritorial | 2021 |
| Natterjack Care Limited | Extraterritorial | 2014 |
| Natty's Enterprise Limited | Wholesale & retail | 2023 |
| Natural Burial (UK) Limited | Other services | 2013 |
| Natural Burial Authority | Education | 2015 |
| Natural Craft Landscapes Ltd | Administrative & support | 2024 |
| Natural Distribution (Holdings) Limited | Professional & scientific | 2003 |
| Natural Distribution Properties Limited | Real estate | 2009 |
| Natural Group Ltd | Manufacturing | 2025 |
| Natural Health Ltd | Wholesale & retail | 2008 |
| Natural Health Wholesale Ltd | Wholesale & retail | 2020 |
| Natural Sante Limited | Professional & scientific | 2013 |
| Natural Wine Bars Limited | Professional & scientific | 2010 |
| Nature Metrics Ltd | Professional & scientific | 2014 |
| Naughty Nectar Ltd | Manufacturing | 2026 |
| Naughty PIG Productions Ltd | Information & communication | 2026 |
| Navien UK Ltd | Wholesale & retail | 2014 |
| NB Resi Consulting Ltd | Professional & scientific | 2024 |
| Nbkb Ltd | Hospitality | 2020 |
| NCA Engineering Limited | Professional & scientific | 2025 |
| ND Organisational Dynamics Ltd | Professional & scientific | 2025 |
| ND Realtors Ltd | Real estate | 2019 |
| ND SG Shop Limited | Wholesale & retail | 2020 |
| NDY Tomorrows CIC | Education | 2025 |
| Neat Freaks Ltd | Administrative & support | 2024 |
| Nebula Cloud Limited | Information & communication | 2015 |
| Nebula Triathlon Team Limited | Arts & recreation | 2025 |
| Neddy Properties Limited | Real estate | 2020 |
| Nedyor 24 Ltd | Construction | 2024 |
| Needsuper Limited | Wholesale & retail | 1986 |
| Neek Dent Care Limited | Health & social care | 2014 |
| Neighbours Welcome | Health & social care | 2022 |
| Neil Buxton Limited | Administrative & support | 2003 |
| Neil Jones Media Consulting Ltd | Professional & scientific | 2012 |
| NEL Global Ltd | Professional & scientific | 2024 |
| Nela Ltd | Professional & scientific | 2024 |
| Nell Ball Farm Limited | Agriculture & fishing | 2007 |
| Nelly's Farm Foods Ltd | Manufacturing | 2021 |
| Nelson Property Services (Southern) Limited | Extraterritorial | 2011 |
| NEO Asteri Ltd. | Administrative & support | 2025 |
| Neoarmor Ltd | Wholesale & retail | 2025 |
| Neocol Group Limited | Professional & scientific | 2012 |
| Neocol UK Ltd | Information & communication | 2003 |
| Neotex UK Ltd | Wholesale & retail | 2017 |
| Nest Made Limited | Real estate | 2023 |
| Nestlenook Investments Limited | Real estate | 2020 |