| Mcginn Advisory Partners Limited | Professional & scientific | 2025 |
| Mcguinness Kitchens Ltd | Construction | 2023 |
| MCI Systems Ltd | Information & communication | 2002 |
| Mclaren Wealth Management UK Limited | Financial services | 2017 |
| MCS Events and Communications Ltd | Administrative & support | 2022 |
| MD Sarah Limited | Wholesale & retail | 2025 |
| MDH Roofing Limited | Construction | 2008 |
| Mdho Limited | Administrative & support | 2016 |
| MDR Design Limited | Professional & scientific | 2018 |
| Mdrr Ltd | Health & social care | 2016 |
| MDT Property Consultants Ltd | Administrative & support | 2010 |
| Mdvh Limited | Wholesale & retail | 2026 |
| ME Developments (Castle Hill) Limited | Construction | 2018 |
| ME Developments (Long Sutton) Limited | Construction | 2018 |
| ME Developments (Upton Grey) Limited | Construction | 2019 |
| ME Dockenfield Development Limited | Construction | 2018 |
| ME Dockenfield Holdings Limited | Construction | 2017 |
| ME Estate Agents (Alton) Limited | Real estate | 2017 |
| ME Estate Agents (ASH Vale) Limited | Real estate | 2018 |
| ME Estate Agents (Worplesdon Road) Limited | Real estate | 2007 |
| ME Estate Agents Holdings Limited | Real estate | 2014 |
| ME Landscapes & Homes Limited | Administrative & support | 2017 |
| ME Tannery Holdings Limited | Real estate | 2017 |
| Meadowside Osteopathy Ltd | Health & social care | 2022 |
| Mechelectrical Ltd | Professional & scientific | 2022 |
| Media Magnifique Limited | Professional & scientific | 2010 |
| Media Revenue Services Limited | Information & communication | 2004 |
| MEDIA2U Limited | Information & communication | 2006 |
| Medical Lifesigns Limited | Education | 2009 |
| Medicmay Ltd | Health & social care | 2021 |
| Medrx Distribution Limited | Professional & scientific | 2011 |
| Medrx Licences Limited | Professional & scientific | 2016 |
| Medsa Animal Health Ltd | Professional & scientific | 2001 |
| Medsa Development Ltd | Professional & scientific | 2016 |
| Medsa Group Limited | Professional & scientific | 2004 |
| Medsa Research Ltd | Professional & scientific | 2003 |
| Medsim Construction Ltd | Construction | 2019 |
| Medstead Physical Health Limited | Health & social care | 2021 |
| Mekong Manufacturing (2011) LLP | | 2011 |
| Melbury Oak Limited | Professional & scientific | 2015 |
| Melia Dance Limited | Arts & recreation | 2009 |
| Melior Strategic Capital Ltd | Financial services | 2019 |
| Melior Tax Limited | Professional & scientific | 2017 |
| Melior Ventures Ltd | Financial services | 2023 |
| Mellow Acoustics Limited | Manufacturing | 2011 |
| Melt Melt Farnham Ltd | Wholesale & retail | 2025 |
| Meltaway Management Company Limited | Households | 1988 |
| Melville Villas Limited | Real estate | 2011 |
| Melvyn Gill Marketing Limited | Professional & scientific | 1984 |
| Membership Matters Training & Consulting Limited | Professional & scientific | 2010 |
| Menace Productions Ltd | Information & communication | 2017 |
| Mendip Skyline (SS) Ltd | Real estate | 2024 |
| Menumagic Ltd | Hospitality | 2019 |
| Meraki Creative Therapies Limited | Administrative & support | 2018 |
| Mercury Prestige Vehicles Limited | Wholesale & retail | 2012 |
| Meriden Pool LLP | | 2017 |
| Meridian Auto Limited | Wholesale & retail | 2016 |
| Merlin Estates Company Secretary Limited | Households | 2016 |
| Merlin Estates Ltd | Real estate | 2011 |
| Merlin House (Chiswick) Management Company Limited | Households | 2015 |
| Merlin Property Stone Limited | Construction | 2022 |
| Merralls Investments Ltd | Hospitality | 2007 |
| Merrow Tyre and Alignment Centre Limited | Wholesale & retail | 1985 |
| Mesh Energy Limited | Professional & scientific | 2015 |
| Meshwork Global Ltd | Education | 2022 |
| Metascape Limited | Extraterritorial | 2026 |
| Meters Electromechanical Services Ltd | Professional & scientific | 2021 |
| Meticulous Mentoring Limited | Health & social care | 2024 |
| Metis Strategic Consulting Ltd | Professional & scientific | 2025 |
| Metsscape Limited | Extraterritorial | 2025 |
| MEW Events Ltd | Professional & scientific | 2016 |
| MEWS24 Ltd | Professional & scientific | 2022 |
| MFC IT Services Ltd | Information & communication | 2019 |
| MG Farnham Ltd | Other services | 2018 |
| MGC001 SPV Ltd. | Construction | 2025 |
| Mhbf Investments Limited | Real estate | 2018 |
| Miabella Limited | Other services | 2002 |
| Michael LEE Architects Limited | Professional & scientific | 2008 |
| Mick Smith Heating & Plumbing Ltd. | Construction | 2003 |
| Micro Radar Ltd | Professional & scientific | 2022 |
| Microsure Ltd | Information & communication | 2005 |
| Middleton Consultants Ltd | Professional & scientific | 2022 |
| Midhurst Windows & Doors Limited | Manufacturing | 2019 |
| Mike Ferguson Consultancy Ltd | Health & social care | 2018 |
| Mike Mcginn Audio Limited | Information & communication | 2020 |
| Mike Neal Ltd | Financial services | 2012 |
| Mike Pink Ltd | Information & communication | 2014 |
| Mike Sparrow Consulting Ltd. | Professional & scientific | 2014 |
| Milbury Foodservice Limited | Wholesale & retail | 2018 |
| Miles Group Holdings Ltd | Financial services | 2025 |
| Milestones Clinic Limited | Health & social care | 2007 |
| Milewski Limited | Construction | 2007 |
| Miley Investments Ltd | Real estate | 2026 |
| Milford Garden Centre Limited | Wholesale & retail | 2013 |
| Milk Club Deliveries Ltd | Hospitality | 2021 |
| Milkdromeda Limited | Construction | 2021 |
| Mill House Events Farnham Ltd | Real estate | 2024 |
| Millbridge Energy Ltd | Professional & scientific | 2010 |
| Millburt Electrical Ltd | Construction | 2021 |
| Miller Camera Support Limited | Professional & scientific | 2006 |