| MSH Property Group Ltd | Construction | 2024 |
| Msport Active Limited | Professional & scientific | 2024 |
| Mssng Ltd | Information & communication | 2024 |
| Msssd Investments Limited | Financial services | 2024 |
| Mstar Space Ltd | Professional & scientific | 2023 |
| Mtech Homes Ltd | Construction | 2022 |
| MTM Elevators Ltd | Construction | 2022 |
| Mtns Properties Ltd | Real estate | 2012 |
| MTS Trucking Ltd | Transport & logistics | 2016 |
| Much Marcle Limited | Financial services | 2016 |
| Muddy Boots Cottages Ltd | Hospitality | 2024 |
| Mudhopper Creative Ltd | Information & communication | 2024 |
| Muir Enterprises Limited | Information & communication | 2013 |
| Mulberry House Management RTM Company Limited | Real estate | 2013 |
| Mulberry Local Authority Services Ltd | Professional & scientific | 2024 |
| Mulberry Secretarial Services Limited | Extraterritorial | 2005 |
| Mullany Limited | Wholesale & retail | 2011 |
| Multigerm UK Enterprises Ltd | Manufacturing | 1997 |
| Multilec UK Limited | Construction | 2005 |
| Multipulse Electronics Limited | Manufacturing | 1984 |
| Munis Pharma Limited | Wholesale & retail | 2024 |
| Munitus Services Limited | Information & communication | 2025 |
| Munro and Partners Ltd | Professional & scientific | 2011 |
| Muntlan Capital Limited | Real estate | 2020 |
| Murata Corporate Relocations Ltd | Real estate | 2023 |
| Murray & Co. Accountants Ltd | Professional & scientific | 2002 |
| Murvagh Group Limited | Construction | 2023 |
| Murvagh Group South Limited | Construction | 2024 |
| Mushroom Joinery Ltd | Construction | 2014 |
| Mvquantum Limited | Wholesale & retail | 2016 |
| MW Farnham Property Holdings Limited | Real estate | 2020 |
| MW HR Services Limited | Administrative & support | 2024 |
| MWR Property (Dene END) Ltd | Construction | 2021 |
| My Business Online Ltd | Professional & scientific | 2020 |
| My Invoice Factoring Limited | Financial services | 2012 |
| My Little Princess Ltd | Other services | 2010 |
| My Source Ltd | Construction | 2018 |
| Mybulk Limited | Information & communication | 2023 |
| Mybutler Consulting Ltd | Professional & scientific | 2025 |
| Mycampusx Ltd | Information & communication | 2021 |
| Mycena Group Limited | Financial services | 2024 |
| Mycena Power Solutions Limited | Construction | 2025 |
| Mycena Renewables Limited | Construction | 2025 |
| Mykeyfinder Ltd | Wholesale & retail | 2013 |
| Myriad Quant Ltd | Information & communication | 2020 |
| N a Bristow Limited | Health & social care | 2003 |
| N L Crabbe Limited | Construction | 2019 |
| N. W. Recruitment Limited | Administrative & support | 2010 |
| N.D.C. Limited | Information & communication | 1988 |
| N.D.Y. Coach Sales Limited | Wholesale & retail | 1977 |
| N.J. Ascott Carpentry & Building Ltd | Construction | 2014 |
| Nails & Spa Farnham Limited | Other services | 2025 |
| Naquara Limited | Professional & scientific | 1994 |
| Narrabane Ltd | Construction | 2023 |
| Nasab Investments Limited | Real estate | 2025 |
| Nash Electrical Services Farnham Ltd | Construction | 2026 |
| Nason Bell Ltd | Professional & scientific | 2024 |
| Nasrani Documentation Services Limited | Information & communication | 2013 |
| Natalia Design Ltd | Professional & scientific | 2019 |
| Nationcare Limited | Construction | 2019 |
| Nationcare Property Services Ltd | Administrative & support | 2008 |
| Nationcare Windows Limited | Wholesale & retail | 2006 |
| Natta Building Company Limited | Construction | 1972 |
| Natta Civils Limited | Construction | 2018 |
| Natta Country Homes (Southern) Limited | Construction | 2001 |
| Natta Country Homes Limited | Construction | 1982 |
| Natta Developments Limited | Construction | 2018 |
| Natta Geo-Environmental Limited | Construction | 2018 |
| Natta Plant Limited | Administrative & support | 1988 |
| Natta Services Limited | Construction | 2018 |
| Natty Drycleaning Limited | Other services | 2026 |
| Natty Tailoring Limited | Other services | 2019 |
| Natuca Ltd | Construction | 2026 |
| Natural Acuity Limited | Wholesale & retail | 2012 |
| Natural Analysis Limited | Information & communication | 2017 |
| Natural Habitat Holdings Ltd | Professional & scientific | 2026 |
| Natural Intellectual Limited | Professional & scientific | 2013 |
| Nature Capital Partners Ltd | Agriculture & fishing | 2024 |
| NAY Bellamy Ltd | Arts & recreation | 2024 |
| NBB Auto Group Ltd | Transport & logistics | 2025 |
| NC IT Consulting Ltd | Information & communication | 2025 |
| NDC IT & Leisure Ltd | Manufacturing | 1998 |
| NDP Property Limited | Real estate | 2012 |
| Ndpc Limited | Hospitality | 2021 |
| Neat Drinks Ltd | Wholesale & retail | 2026 |
| Nebula Productions Ltd | Arts & recreation | 2012 |
| Nekton Films Limited | Information & communication | 2014 |
| Nelson Associates Limited | Professional & scientific | 2007 |
| Nelson Devereux Consultancy Limited | Professional & scientific | 2025 |
| Neobuild Ltd | Construction | 2025 |
| Nest Forest Ltd | Manufacturing | 2023 |
| Netmean Limited | Information & communication | 2000 |
| Network Professionals Limited | Information & communication | 1996 |
| Networking Hampshire Ltd | Other services | 2014 |
| Neural Aspect Ltd | Information & communication | 2024 |
| Never Fear Truth Limited | Extraterritorial | 2022 |
| New Adventures Charity | Education | 2008 |
| New Country Estates Ltd | Construction | 2020 |
| New END Books Ltd. | Professional & scientific | 2003 |
| New Group Ltd | Construction | 2019 |