| Mantra Living Kitchens Ltd | Construction | 2025 |
| Mantra Living Limited | Construction | 2021 |
| Mantra Living Shop Ltd | Wholesale & retail | 2025 |
| Mantraq Limited | Real estate | 2003 |
| Manu Stone Ltd | Professional & scientific | 2025 |
| Manufacturing Delivery Management Services Ltd | Professional & scientific | 2021 |
| MAP Print Limited | Wholesale & retail | 2017 |
| Maple & Key Properties Limited | Real estate | 2025 |
| Maple Advisors Limited | Professional & scientific | 2014 |
| Maple Connect Finance Limited | Financial services | 2022 |
| Maple Finance Ltd | Financial services | 2026 |
| Maple Mortgage Services Ltd | Financial services | 2019 |
| Maple Properties Services Ltd | Real estate | 2017 |
| Mara Nexus Ltd | Wholesale & retail | 2025 |
| Marbellous Solutions Ltd | Manufacturing | 2025 |
| Marble Cleaning Ltd | Construction | 2016 |
| Marble Design Studio Ltd | Manufacturing | 2021 |
| Marble Memories Ltd | Professional & scientific | 2024 |
| Marc's Property Maintenance Ltd | Construction | 2021 |
| Marci International Ltd | Wholesale & retail | 2015 |
| Marcus Court Residents Association Limited | Households | 1997 |
| Marcus Drake Property Services Ltd | Construction | 2013 |
| Marden Consulting Limited | Professional & scientific | 2021 |
| Marden Wolfe Limited | Other services | 1978 |
| Marden Wolfe Packaging Limited | Other services | 1990 |
| Mardle Holdings Ltd | Other services | 2008 |
| Margi Ltd | Construction | 2019 |
| Margo Perkins Limited | Professional & scientific | 2022 |
| Maria Gemenetzi Consultancy Ltd | Health & social care | 2026 |
| Marick Management Ltd | Administrative & support | 2012 |
| Marick Trustee Limited | Professional & scientific | 2022 |
| Marieli Equestrian Ltd | Wholesale & retail | 2020 |
| Marina Dieck Ltd | Professional & scientific | 2009 |
| Marine Advisory & Technical Consultants Limited | Professional & scientific | 1984 |
| Marisor Logistics Ltd | Transport & logistics | 2024 |
| Market Royale Limited | Extraterritorial | 2013 |
| Marketing & Creative Search Consultants Limited | Information & communication | 2014 |
| Marketing Point Limited | Professional & scientific | 2007 |
| Marketing Valley Ltd | Professional & scientific | 2019 |
| Marketplan Marketing Services Group Limited | | 1974 |
| Marlin Estates Limited | Real estate | 1987 |
| Marlin Mansion Limited | Real estate | 2020 |
| Marlink Limited | Information & communication | 2004 |
| Marmalade Consulting Limited | Professional & scientific | 2018 |
| Marotori Limited | Information & communication | 2002 |
| Marouk Consulting Ltd | Agriculture & fishing | 2017 |
| Mars & Minerva Shooting Club Ltd | Extraterritorial | 2006 |
| Marsh Bowles Limited | Hospitality | 2021 |
| Marshal Facility Management Ltd | Administrative & support | 2018 |
| Marshstar Limited | Real estate | 1996 |
| Marspares Services Ltd. | Professional & scientific | 1996 |
| Martels-Uk Ltd | Real estate | 2022 |
| Martin Irwin Consulting Engineers Ltd | Professional & scientific | 2025 |
| Martin O'Connor Installation Services Ltd | Construction | 2022 |
| Marvel Cleaning Services Ltd | Administrative & support | 2021 |
| Mary D Beauty Ltd | Other services | 2024 |
| Mary Samu Ltd | Health & social care | 2025 |
| Mary’S Mobile Chef Services Ltd | Manufacturing | 2020 |
| Masala Kingdom Ltd | Hospitality | 2024 |
| Mashauri Limited | Education | 2013 |
| Masila Limited | Hospitality | 2016 |
| Maskateer Limited | Wholesale & retail | 2017 |
| Mason Healthcare Ltd | Health & social care | 2015 |
| Master Roofing & Building Ltd | Construction | 2018 |
| Masud & Shah Ltd | Hospitality | 2025 |
| Matbridge Projects Ltd | Construction | 2024 |
| Matchico Ltd | Information & communication | 2025 |
| Mathew Webb Property Investment Limited | Real estate | 2025 |
| Maths Properties Limited | Real estate | 2025 |
| Matoorian Limited | Real estate | 2014 |
| Matt & Liam Creative Limited | Professional & scientific | 2019 |
| Matthew Grahame Limited | Construction | 2014 |
| Matthew Stone Ltd. | Professional & scientific | 2015 |
| Maurice Nash Welding Ltd | Administrative & support | 2015 |
| Maverick I Ltd | Professional & scientific | 2008 |
| Mawha Management Ltd | Professional & scientific | 2019 |
| Maxim Cloud Ltd | Information & communication | 2026 |
| Maxima Markets Limited | Wholesale & retail | 2015 |
| Maximise Accounting Ltd | Professional & scientific | 2021 |
| Maximus Mediascape Ltd | Information & communication | 2024 |
| Maxroc Advisory Limited | Financial services | 2026 |
| Maxroc Insurance Holdings Limited | Financial services | 2015 |
| Maxted Building Consultancy Ltd | Professional & scientific | 2026 |
| Maxwell Watts Limited | Professional & scientific | 2017 |
| MAY Creative Ltd | Professional & scientific | 2016 |
| MAY K Limited | Real estate | 1970 |
| MAY Personnel Limited | Administrative & support | 2012 |
| Mayaell Ltd | Wholesale & retail | 2017 |
| Maybury and Sheerwater Community Trust | Health & social care | 2011 |
| Maybury Court (Woking) RTM Company Limited | Households | 2004 |
| Maybury Guitars Ltd | Manufacturing | 2019 |
| Maybury House Management Limited | Households | 1987 |
| Maybury IT Limited | Information & communication | 2017 |
| Maybury Knowle Management Company Limited | Households | 2001 |
| Maycroft Limited Partnership | | 2010 |
| Mayen Spice Limited | Hospitality | 2024 |
| Mayer Brown Limited | Professional & scientific | 1998 |
| Mayer Enterprises Limited | Administrative & support | 2015 |
| Mayfair Apartments (U.K.) Limited | Real estate | 1986 |
| Mayfair Development (U.K.) Limited | Real estate | 1986 |