| MBC Automotive Ltd | Professional & scientific | 2018 |
| MBM Porter Ltd | Real estate | 2018 |
| MC Kaizen Limited | Financial services | 2015 |
| Mcben Developments Ltd | Construction | 2021 |
| Mcben Group Ltd | Financial services | 2024 |
| Mcben Properties Limited | Construction | 2024 |
| Mccolton Ltd | Professional & scientific | 2017 |
| Mccormick Accounting Limited | Professional & scientific | 2019 |
| MCH Lettings Ltd | Real estate | 2025 |
| Mcintosh Law Limited | Professional & scientific | 2010 |
| Mckenzie Attwood Limited | Information & communication | 1995 |
| Mclaren International Ltd | Real estate | 2026 |
| Mclellan Medical Ltd | Health & social care | 2026 |
| Mcqueenspeech Ltd | Health & social care | 2014 |
| Mcsheffrey Holdings Limited | Financial services | 2021 |
| MD Fighting Spirit Limited | Arts & recreation | 2018 |
| MDC Equestrian Ltd | Wholesale & retail | 2025 |
| Mdxpress Limited | Transport & logistics | 2015 |
| Medatis Ltd | Health & social care | 2019 |
| Meditate Place Ltd | Health & social care | 2017 |
| Mehmet 1 Ltd | Hospitality | 2026 |
| Meiklejohn Graphics Licensing Limited | Arts & recreation | 1997 |
| Melbourne Cafe Limited | Hospitality | 2018 |
| Meliora Properties Ltd | Extraterritorial | 2020 |
| Melissa Trindade Limited | Information & communication | 2019 |
| Mellona Ltd | Transport & logistics | 2019 |
| Mellor Management Company Limited | Households | 2013 |
| Melodi Limited | Information & communication | 2002 |
| Melodi WIN (Ireland) Ltd | Arts & recreation | 2026 |
| Melodi WIN Ltd | Arts & recreation | 2024 |
| Mend and Sewing Limited | Other services | 2026 |
| Menear Engineering Ltd | Manufacturing | 2014 |
| Mensa Slade Limited | Real estate | 2020 |
| Mentorcloud Ltd | Professional & scientific | 2025 |
| Merch Better Ltd | Professional & scientific | 2022 |
| Mercia Carpentry Limited | Manufacturing | 2025 |
| Mercia Dental Equipment Limited | Wholesale & retail | 2008 |
| Mercia Farmers' Market Ltd | Hospitality | 2022 |
| Mercia Property Investments (UK) Ltd | Construction | 2025 |
| Mercia Workshop Ltd | Manufacturing | 2023 |
| Mercian Community Trust | Other services | 2001 |
| Mercian Science Limited | Professional & scientific | 1998 |
| Merit Technology (UK) Limited | Information & communication | 2013 |
| Merlin Business Software Limited | Information & communication | 1976 |
| Merlin Catering & Refrigeration Ltd | Manufacturing | 2015 |
| Merlin Floors & Ceramics Limited | Construction | 2001 |
| Merricot Ltd | Other services | 2017 |
| Merstow Ltd | Administrative & support | 2026 |
| Metaco Commodities Limited | Real estate | 2015 |
| Metaco Construction Limited | Construction | 2020 |
| Metalicouk Limited | Wholesale & retail | 1990 |
| Metis Developments Limited | Construction | 2012 |
| Metro Discount Stores (Midlands) Limited | Extraterritorial | 1975 |
| Mexfield Property Solutions Limited | Professional & scientific | 2025 |
| Meya Limited | Professional & scientific | 2010 |
| Mezzanines and Storage Equipment Limited | Construction | 2017 |
| MG Land Ltd | Construction | 2026 |
| Mg&E Limited | Information & communication | 2013 |
| MGH Professional Limited | Professional & scientific | 2014 |
| MGI (Cotswolds) Limited | Real estate | 2022 |
| MGM Building Projects Limited | Administrative & support | 2022 |
| MGM Electrics Midlands Ltd | Construction | 2020 |
| MHB Solutions Ltd | Administrative & support | 2020 |
| MHD Comm Holdings Limited | Real estate | 2020 |
| MHO Power Services Ltd | Energy | 2024 |
| Mhsta Solutions Limited | Information & communication | 2024 |
| MIA Developments Limited | Construction | 2017 |
| Miami Boss Co. Ltd | Wholesale & retail | 2024 |
| Micap Consulting Ltd | Professional & scientific | 2024 |
| Micap Developments Ltd | Construction | 2024 |
| Micap Group Ltd | Construction | 2022 |
| Micap Litigation Ltd | Financial services | 2024 |
| Micap Recruitment Ltd | Administrative & support | 2024 |
| Michael Communications Ltd | Information & communication | 2023 |
| Michael Mckiernan Agencies Limited | Wholesale & retail | 2018 |
| Michael Riley Sound Engineering Company Ltd | Arts & recreation | 2014 |
| Michael's Menswear Limited | Wholesale & retail | 2010 |
| Michelle Usher Hair Ltd | Other services | 2019 |
| Michelle Wheatley Associates Ltd | Administrative & support | 2023 |
| Micropower Computer Limited | Administrative & support | 2013 |
| Micropower Space Ltd | Manufacturing | 2005 |
| Midcounties Blacking Limited | Arts & recreation | 2015 |
| Middleton Equestrian Centre Limited | Arts & recreation | 1995 |
| Midland Auto-Electrical Company (Lichfield) Limited(The) | Wholesale & retail | 1952 |
| Midland Compressed Air Ltd | Construction | 2009 |
| Midland Creative Paving & Landscaping Ltd | Administrative & support | 2024 |
| Midland Dairy Chemicals Ltd | Wholesale & retail | 2021 |
| Midland FOX Capital Ltd | Real estate | 2018 |
| Midland Funeral Supplies Limited | Manufacturing | 1977 |
| Midland Motorways Group Limited | Professional & scientific | 2006 |
| Midland Physiotherapy Ltd | Other services | 2025 |
| Midland Property Maintenance Limited | Administrative & support | 2013 |
| Midland Vauxhall Breakers Limited | Wholesale & retail | 2011 |
| Midlands Car & Van Leasing Ltd | Wholesale & retail | 2006 |
| Midlands Damp Proofing Ltd | Construction | 2024 |
| Midlands HIP & Knee Ltd | Health & social care | 2025 |
| Midlands Infant Feeding Limited | Health & social care | 2023 |
| Midlands Upper Limb Surgery Ltd | Health & social care | 2023 |
| Midlands Veterinary Ultrasound Ltd | Professional & scientific | 2021 |
| Midpoint Windows Limited | Construction | 2021 |