| MH & N Services Limited | Construction | 2011 |
| MH Business Consultancy Ltd | Information & communication | 2024 |
| MI Solar Ltd | Energy | 2024 |
| MI Solicitors Limited | Professional & scientific | 2015 |
| MIA G Traffic Management Limited | Construction | 2025 |
| Miah Family Investments Limited | Real estate | 2025 |
| Miah Holdings Ltd | Real estate | 2023 |
| Michael a Williams Accountants Limited | Professional & scientific | 2011 |
| Michael Keeling Limited | Professional & scientific | 2013 |
| Michael P Brown Limited | Professional & scientific | 2023 |
| Michaels Chemist Limited | Real estate | 2002 |
| Michelle Worthington Aesthetic Health Ltd | Other services | 2021 |
| Michelle-Ivy Limited | Wholesale & retail | 2024 |
| Mick Mckeogh Technical Support & Training Ltd | Manufacturing | 2020 |
| Microsports Camps Limited | Education | 2020 |
| Microsports Clubs Limited | Education | 2020 |
| Microsports Communities C.I.C. | Arts & recreation | 2026 |
| Microsports Management Limited | Arts & recreation | 2020 |
| Microsports Schools Limited | Arts & recreation | 2015 |
| MID Car Trade Centre Ltd | Wholesale & retail | 2022 |
| MID Sussex Funeral Services Limited | Extraterritorial | 1978 |
| MID Trade Centre Limited | Wholesale & retail | 2025 |
| Midas Education Ltd | Administrative & support | 2026 |
| Midas Recruitment Ltd | Administrative & support | 2010 |
| Midas Recruitment Temp Ltd | Administrative & support | 2010 |
| Midas Selection (Midlands) Ltd | Information & communication | 2003 |
| Midbass Distribution Limited | Wholesale & retail | 2000 |
| Middle Support / Care Homes Ltd | Health & social care | 2010 |
| Middleton & Wood (1919) Limited | Extraterritorial | 1919 |
| Middshaw Finance Limited | Financial services | 2022 |
| Middshaw Limited | Other services | 2018 |
| Midland BIW Pressings Limited | Manufacturing | 2025 |
| Midland Builders Limited | Construction | 2013 |
| Midland Cleaning Services (Birmingham) Limited | Administrative & support | 2024 |
| Midland Cleaning Services (Leicester) Limited | Administrative & support | 2024 |
| Midland Cleaning Services (UK) Limited | Administrative & support | 2010 |
| Midland Consulting Ltd | Construction | 2024 |
| Midland Cylinder Recycling Ltd | Water & waste | 2022 |
| Midland Haulage Limited | Transport & logistics | 2008 |
| Midland Interiors P&D Ltd | Construction | 2020 |
| Midland IR Ltd | Health & social care | 2026 |
| Midland Medical Courses Ltd | Education | 2025 |
| Midland Music Education Services Ltd | Education | 2015 |
| Midland Properties Limited | Agriculture & fishing | 1994 |
| Midland Road Springs Ltd | Wholesale & retail | 2008 |
| Midland Specialist Orthopaedic Services Limited | Health & social care | 2011 |
| Midland Structural Design Ltd | Professional & scientific | 2022 |
| Midland Supply Limited | Wholesale & retail | 2010 |
| Midland Tyres (Birmingham) Limited | Real estate | 1954 |
| Midland Way Ltd | Administrative & support | 2025 |
| Midlands Andrology and Urology Services Limited | Health & social care | 2017 |
| Midlands Bespoke Motors Limited | Construction | 2023 |
| Midlands Bowel Clinic Ltd | Health & social care | 2020 |
| Midlands Brick Pickers Limited | Wholesale & retail | 2015 |
| Midlands Business Finance Solutions Limited | Financial services | 2008 |
| Midlands Engineering (UK) Ltd | Construction | 2013 |
| Midlands Food Ltd | Hospitality | 2026 |
| Midlands Mobile Entry Ltd | Administrative & support | 2025 |
| Midlands Mobility and Rehab Solutions Ltd | Wholesale & retail | 2024 |
| Midlands Motocross Limited | Administrative & support | 2018 |
| Midlands Neuro Paediatric Ltd | Health & social care | 2023 |
| Midlands Psychological Services Limited | Health & social care | 2000 |
| Midlands Quantity Surveying Ltd | Professional & scientific | 2022 |
| Midlands Shockwave and Physiotherapy Clinic Ltd | Other services | 2018 |
| Midlands UK Holdings Ltd | Real estate | 2023 |
| Midlands Utility Solutions Ltd | Construction | 2026 |
| Midlands Wheel Centre Ltd | Wholesale & retail | 2018 |
| Midlands Women's Health Limited | Health & social care | 2023 |
| Midou Limited | Health & social care | 2017 |
| Midprop Investments Ltd | Real estate | 2020 |
| Midsec Limited | Administrative & support | 2008 |
| Midway Enterprise Limited | Professional & scientific | 2003 |
| Miffy LOU Properties Limited | Real estate | 2026 |
| Mighty Motors Limited | Wholesale & retail | 2022 |
| Migliore Clothing Ltd | Wholesale & retail | 2025 |
| Migrace Consultants Limited | Professional & scientific | 2020 |
| Mike Chapman Associates Ltd | Professional & scientific | 2017 |
| Mike Corcoran Ltd | Administrative & support | 2007 |
| Mike Nicklin Consultancy Services Limited | Professional & scientific | 2016 |
| Mike Weaver Communications Limited | Information & communication | 2000 |
| Mikho Limited | Hospitality | 2025 |
| Military Chef Events Ltd | Hospitality | 2025 |
| Military Chef Ltd | Hospitality | 2022 |
| Milk River Limited | Professional & scientific | 2010 |
| Milk Yard Trading Co Ltd | Hospitality | 2025 |
| Mill Road Flats Management Company Limited | Households | 2003 |
| Millies Cleaning Company Limited | Administrative & support | 2025 |
| Million Mobiles Ltd | Wholesale & retail | 2024 |
| Milloak Property Ltd | Real estate | 2024 |
| Millrock Limited | Real estate | 2016 |
| Milner Industrial Ltd | Wholesale & retail | 2009 |
| Milner Industrial Systems Ltd | Wholesale & retail | 2026 |
| Milo Aesthetics Ltd | Other services | 2020 |
| Milo Productions Ltd | Information & communication | 2025 |
| Milunn Ltd | Wholesale & retail | 2022 |
| Mind Fitness Hub Ltd | Health & social care | 2020 |
| Mind Over Muscle Ltd | Wholesale & retail | 2025 |
| Mind the Brain Limited | Professional & scientific | 2019 |
| Mindcalm Ltd | Health & social care | 2015 |
| Mindful HR Solutions Limited | Administrative & support | 2017 |