| Martin Jordan Limited | Administrative & support | 2002 |
| Martingales Residents Management Company Limited | Households | 2019 |
| Masonry Support Systems Limited | Manufacturing | 2014 |
| Massuk Ltd | Administrative & support | 2025 |
| MAT MAD Ltd | Manufacturing | 2014 |
| Materials Handling Products Limited | Manufacturing | 1991 |
| Matt Taylor Plumbing and Heating Limited | Construction | 2024 |
| Matthew Glyn Perkins Limited | Extraterritorial | 2024 |
| Matthew Mayne & Co Ltd | Professional & scientific | 2012 |
| Maureen MAY Scott Limited | Extraterritorial | 2023 |
| Maurlea Inns Ltd | Hospitality | 2025 |
| Maximus Strategic Warmley Limited | Real estate | 2014 |
| Maxine Adams Consultancy Ltd | Public administration | 2023 |
| Maya Marco Ltd | Professional & scientific | 2022 |
| Maya Marco Property Ltd | Real estate | 2023 |
| Mayfield & Jacobs Limited | Wholesale & retail | 2025 |
| Mayfield Accountants Limited | Professional & scientific | 2025 |
| MBT Property Services Ltd | Construction | 2013 |
| MBX Services Limited | Other services | 2020 |
| Mccausland Contractors Ltd | Construction | 2014 |
| Mckenna Media Ltd | Other services | 2026 |
| Mcklane Building Ltd | Construction | 2025 |
| MCN Property Ltd | Real estate | 2020 |
| Mcneil & Rowe Ltd | Wholesale & retail | 2024 |
| MD Customs Ltd | Wholesale & retail | 2025 |
| MDL Solutions Ltd | Professional & scientific | 2023 |
| MDS Property Limited | Real estate | 2010 |
| ME Motors (Burton) Ltd | Wholesale & retail | 2026 |
| ME Social HQ Limited | Information & communication | 2026 |
| ME Training & Development Ltd | Education | 2017 |
| Meadow Brook (Hilton) Management Company Limited | Households | 2005 |
| Meadow View (Hill Ridware) Management Company Limited | Households | 2018 |
| Mease Valley Potatoes Limited | Agriculture & fishing | 2003 |
| Mease Valley Properties Limited | Real estate | 2023 |
| Measham Barber Ltd | Other services | 2025 |
| Measham Dental Limited | Health & social care | 2014 |
| Measham Events CIC | Administrative & support | 2023 |
| Measham EYE Care Limited | Health & social care | 2016 |
| Measham Top Club Bar Ltd | Hospitality | 2025 |
| Measham Vapes and Booze Limited | Wholesale & retail | 2025 |
| Measham Wholesale Limited | Wholesale & retail | 2017 |
| Measom Building Services Ltd | Construction | 2002 |
| Medical Outreach Services Ltd | Health & social care | 2023 |
| Medisys International Limited | Administrative & support | 2016 |
| Meditap Ltd | Wholesale & retail | 2025 |
| Meeple Market Limited | Wholesale & retail | 2023 |
| Mega Munch Ltd | Hospitality | 2025 |
| Megnesmedia Ltd | Professional & scientific | 2025 |
| MEL Evans Bulk Haulage Limited | Transport & logistics | 2002 |
| Melody Joan Ltd | Wholesale & retail | 2025 |
| Memz Healthcare Ltd | Health & social care | 2023 |
| Mercer Grove (Bromsgrove) Management Company Limited | Households | 2016 |
| MERY97 Ltd | Transport & logistics | 2022 |
| Metal Mickys LGV Driver Training Limited | Administrative & support | 2017 |
| Metre Capital Advisors (Midlands) Limited | Administrative & support | 2026 |
| Metric Glazing Systems Ltd | Manufacturing | 2023 |
| Metric Interior Systems Ltd | Construction | 2019 |
| Metric M&E Solutions Limited | Construction | 2015 |
| Metric Ventures Limited | Financial services | 2021 |
| MG Composites and Consultancy Ltd | Professional & scientific | 2023 |
| MG Haulage Ltd | Transport & logistics | 2020 |
| MG Obsession Workshop Ltd | Wholesale & retail | 2017 |
| MHS Plastering Ltd | Construction | 2023 |
| Micron Holdings 1664 Ltd | Professional & scientific | 2026 |
| MID Transport Ltd | Transport & logistics | 2016 |
| Mid-Anglia Project Engineering Limited | Real estate | 1970 |
| Midland Facilities Management Ltd | Energy | 2020 |
| Midland Lead Holdings Ltd | Administrative & support | 2016 |
| Midland Lead Ltd | Wholesale & retail | 2012 |
| Midland Shipping Company Ltd | Transport & logistics | 2022 |
| Midland Waste Services Ltd | Construction | 2024 |
| Midlands Ambulance Group Ltd | Public administration | 2020 |
| Midlands Construction Products Ltd | Manufacturing | 2015 |
| Midlands Forestry Ltd | Real estate | 2015 |
| Midlands Pest Control Limited | Administrative & support | 2013 |
| Midlandscriticallogistics Ltd | Transport & logistics | 2026 |
| Midlanstransport Ltd | Transport & logistics | 2022 |
| Midleisure Services (Vending) Limited | Wholesale & retail | 2006 |
| Midshires Marine Ltd | Financial services | 2016 |
| Midway Controls Limited | Information & communication | 2015 |
| Midway Engineering Ltd | Construction | 2021 |
| Midway Pre-School | Education | 2007 |
| Mighty TAF Logistics Ltd | Transport & logistics | 2025 |
| Mihtar Limited | Information & communication | 2015 |
| MIJ Brickwork Ltd | Construction | 2026 |
| Mill View Gardens Management Company Limited | Households | 2019 |
| Millers Croft Residents Management Company Limited | Households | 2016 |
| Mimi Spa Limited | Other services | 2007 |
| Mimir Research Group Ltd | Administrative & support | 2021 |
| Mineral Products Electrical Services Limited | Professional & scientific | 2023 |
| Mini Explorers Play School Ltd | Education | 2014 |
| Minorca Holdings Limited | Other services | 2021 |
| Miranth Printing Ltd | Manufacturing | 2026 |
| Mitch Howard Consultancy Ltd | Administrative & support | 2014 |
| MJC Training Ltd | Transport & logistics | 2022 |
| MJD Holdings Limited | Professional & scientific | 2006 |
| Mjirigging Ltd | Construction | 2019 |
| MJJ Property Services Limited | Real estate | 2015 |
| MKB Abodes Limited | Real estate | 2020 |
| MLC Building Services Ltd | Construction | 2021 |