| Mcintyre Design & Build Ltd | Real estate | 2013 |
| Mcje Property Ltd | Real estate | 2021 |
| Mcquilling Partners Limited | Transport & logistics | 2024 |
| Mcrw Limited | Wholesale & retail | 1986 |
| MD12 Limited | Administrative & support | 2014 |
| MDS Electrical and Mechanical Ltd | Manufacturing | 2024 |
| Meadland Estates Limited | Professional & scientific | 2012 |
| Meadows & Passmore Limited | Wholesale & retail | 1995 |
| Meadside Freeholders Limited | Real estate | 1974 |
| Meddings Effects Limited | Arts & recreation | 2008 |
| Meddx 650 Limited | Manufacturing | 2020 |
| Meddx Services Limited | Manufacturing | 2020 |
| Meddx Solutions Limited | Manufacturing | 2013 |
| Meddxtainer Limited | Manufacturing | 2020 |
| Media Ferret Ltd | Information & communication | 2015 |
| Medispatch Ltd | Transport & logistics | 2020 |
| Meditex Support UK Limited | Information & communication | 2016 |
| Medium Rare Promotions Limited | Administrative & support | 2003 |
| Medway Giles Ltd | Professional & scientific | 2024 |
| Medwyn Occupational Health Limited | Health & social care | 2020 |
| Megan MAY Pilates Ltd | Arts & recreation | 2024 |
| Melorium Clocks & Antiques Ltd | Wholesale & retail | 2023 |
| Membermojo Limited | Information & communication | 2014 |
| Menkind Digital Limited | Wholesale & retail | 2019 |
| Menkind Group Limited | Extraterritorial | 2016 |
| Menkind Limited | Wholesale & retail | 2001 |
| Menkind Properties UK Limited | Extraterritorial | 2013 |
| Menkind Retail Limited | Wholesale & retail | 2016 |
| Menkind Seasonal Limited | Administrative & support | 2009 |
| Menkind Stores Limited | Wholesale & retail | 2016 |
| Meredith Brodie Design LLP | | 2012 |
| Merrick Place Limited | Households | 1992 |
| Merrylands Court Residents Association (Bookham) Limited | Households | 1984 |
| Mertinga Management Company Limited | Households | 1981 |
| Metropolis Management Company Limited | Households | 1993 |
| Metz Maritime Limited | Transport & logistics | 2022 |
| MG Associates (UK) Limited | Professional & scientific | 2014 |
| MG Firetech Ltd | Administrative & support | 1999 |
| MG Interior Solutions Limited | Construction | 2015 |
| MH Media Productions Ltd | Professional & scientific | 2021 |
| Mhgcat Limited | Other services | 2017 |
| Mhor Studio Limited | Professional & scientific | 2024 |
| Michael Alborough Consulting Ltd | Professional & scientific | 2011 |
| Michael Coughlin Associates Limited | Professional & scientific | 2024 |
| Michael Eaton Services Limited | Professional & scientific | 2016 |
| Michael Roberts Scenic Artist Ltd | Arts & recreation | 2020 |
| Michael Thwaites Consultants Limited | Administrative & support | 2005 |
| Micksco Training Consultants Ltd | Professional & scientific | 2020 |
| Microtech Communications Limited | Information & communication | 2001 |
| MID Surrey Community Fridges CIC | Water & waste | 2019 |
| Middle Green (Flats) Limited | Other services | 1992 |
| Middle Green (Management) Limited | Other services | 1992 |
| Middle Street Management Company Limited | Extraterritorial | 2012 |
| Miguel Ruano Associates Limited | Professional & scientific | 2010 |
| Mikado Resources Limited | Administrative & support | 2006 |
| Mike MAY Construction Limited | Professional & scientific | 2017 |
| Mill House Residents Company Limited | Households | 2016 |
| Millennium Coaches Limited | Transport & logistics | 1999 |
| Milton Court (Wandsworth) Residents Company Limited | Households | 1996 |
| Milton Property Management Limited | Real estate | 2001 |
| Mimosa Close Management Company Limited | Real estate | 2016 |
| Minato Ltd | Hospitality | 2019 |
| Minding Your Business Ltd | Administrative & support | 2018 |
| Mindset Communications Limited | Administrative & support | 2003 |
| Minerva Development Services Limited | Construction | 2008 |
| Mini Mayhem Limited | Arts & recreation | 2008 |
| Mint Insurance Brokers Limited | Financial services | 2013 |
| Mirror Mirror Cosmetics Ltd | Wholesale & retail | 2023 |
| Mirtech Cars Ltd | Wholesale & retail | 2024 |
| Mirtech Services Ltd | Wholesale & retail | 2023 |
| MJ Heating & Electrical Limited | Construction | 2016 |
| MJC Wood Design Co. Ltd | Manufacturing | 2025 |
| Mjcav Ltd | Professional & scientific | 2014 |
| MJR Plastering Ltd | Construction | 2023 |
| MK Pearly Smile Limited | Health & social care | 2023 |
| MK Welding and Fabrication Ltd | Manufacturing | 2025 |
| MKL Communications Limited | Administrative & support | 2017 |
| Mlhmedia Ltd | Professional & scientific | 2022 |
| MLT Autos Ltd | Wholesale & retail | 2003 |
| Mobile Barbers @ 134 Ltd | Other services | 2023 |
| Mobius Business Technologies Limited | Information & communication | 2010 |
| Mobius Holdings Limited | Information & communication | 2015 |
| Modena Digital Ltd | Professional & scientific | 2023 |
| Mole Valley Asset Management Ltd | Financial services | 2013 |
| Mole Valley Builders Ltd | Construction | 2018 |
| Mole Valley Plant Hire Ltd | Construction | 2021 |
| Mole Valley Specialist Cars Limited | Wholesale & retail | 2010 |
| Monika Hill Legal Services Ltd | Professional & scientific | 2019 |
| Monks Management Limited | Real estate | 1989 |
| Montanino Limited | Hospitality | 2007 |
| Montilla Digital Ltd | Professional & scientific | 2024 |
| Montpellier Court Residents Company Limited | Households | 2003 |
| Monty's Menus Limited | Hospitality | 2025 |
| Moonwhiskvfx Limited | Information & communication | 2022 |
| Morecambe Antiques Limited | Wholesale & retail | 2003 |
| Morris Court Management Company Limited | Households | 2007 |
| Morris Oddy & Company Limited | Real estate | 1938 |
| Morriss Court Management Limited | Households | 1987 |
| Motofocus Ltd | Information & communication | 2026 |
| Mova Holdings Limited | Professional & scientific | 2016 |