| Mccurdy Estates Ltd | Real estate | 2023 |
| Mcgregor Building Services Ltd | Construction | 2023 |
| Mcgregor Holdco Ltd | Financial services | 2024 |
| Mcguinness Trading Ltd | Wholesale & retail | 2017 |
| Mckenzie Bakes Ltd | Manufacturing | 2025 |
| MCL International Ltd | Construction | 2010 |
| MCL Van Sales Limited | Wholesale & retail | 2005 |
| Mclean Architects Limited | Professional & scientific | 1995 |
| Mcnamara Ltd | Construction | 2015 |
| Mcnif Cuisine Ltd | Hospitality | 2024 |
| Mcpro Consultancy Ltd | Health & social care | 2021 |
| Mcqueens Developments (Midlands) Limited | Construction | 2016 |
| MCS Electrics Ltd | Construction | 2007 |
| MCS Motor Services Limited | Wholesale & retail | 2015 |
| Mcsp Holistics Ltd | Manufacturing | 2025 |
| MD Advisors Limited | Financial services | 2017 |
| Mdcm Limited | Construction | 2004 |
| MDD Discount Sales Ltd | Wholesale & retail | 2023 |
| MDE Sports UK Limited | Wholesale & retail | 2015 |
| MDK Consultancy Ltd | Professional & scientific | 2019 |
| MDL Express Ltd | Transport & logistics | 2019 |
| MDP Associates Limited | Financial services | 2008 |
| Mdsb Property Limited | Households | 2019 |
| ME Healthcare Ltd | Health & social care | 2024 |
| Meadow Face Limited | Wholesale & retail | 2025 |
| Meadowbank Investments Limited | Transport & logistics | 2021 |
| Mearab Mart Ltd | Wholesale & retail | 2025 |
| Mearzan Ltd | Transport & logistics | 2024 |
| Measham Heating and Air-Conditioning Limited | Construction | 1970 |
| Meat Plus Limited | Transport & logistics | 1992 |
| MEB Corporate Services Limited | Professional & scientific | 2019 |
| Mech - Enmark Limited | Construction | 2012 |
| Mech Tech Midland Ltd | Construction | 2015 |
| Mechanical Fire Services Limited | Manufacturing | 2016 |
| Mechanical Repair Centre Limited | Manufacturing | 2014 |
| Mechanicar Ltd | Professional & scientific | 2018 |
| Mechanicool (Midlands) Limited | Wholesale & retail | 2008 |
| Mechtech Solutions Ltd | Professional & scientific | 2025 |
| Medalli Limited | Professional & scientific | 2017 |
| Medbi Limited | Health & social care | 2022 |
| Medepos Limited | Extraterritorial | 2012 |
| Medgram Ltd | Health & social care | 2022 |
| Medi-Call Care 24/7 Ltd | Health & social care | 2020 |
| Medic Optics Ltd | Health & social care | 2018 |
| Medical Holistics Ltd | Health & social care | 2024 |
| Medical Solutions (GB) Ltd | Health & social care | 2015 |
| Medical Solutions GP Services Ltd | Health & social care | 2023 |
| Medical Solutions Management Ltd | Health & social care | 2022 |
| Medicine Cafe Limited | Hospitality | 2023 |
| Medicolegal Practice Ltd | Health & social care | 2018 |
| Medicure Medics Ltd | Health & social care | 2020 |
| Medispax Limited | Other services | 2024 |
| Medition Limited | Wholesale & retail | 2020 |
| Medscan Ltd. | Health & social care | 2014 |
| Medshal Ltd | Health & social care | 2023 |
| Meeku Global Limited | Wholesale & retail | 2025 |
| Meerakul Enterprises Ltd | Professional & scientific | 2018 |
| Meezan Eco Transport Ltd | Transport & logistics | 2025 |
| Meezan Logistics Limited | Transport & logistics | 2023 |
| Meezan Travel & Courier Ltd | Administrative & support | 2022 |
| Mehfil Desserts Ltd | Hospitality | 2026 |
| Mehfil Restaurant & Takeaway Ltd | Hospitality | 2026 |
| Mejakino Ltd | Wholesale & retail | 2025 |
| Meji Holdings Ltd | Real estate | 2017 |
| MEL Evans Construction Limited | Construction | 2015 |
| MEL Imports Limited | Wholesale & retail | 2025 |
| Melanin Magic Enterprises Limited | Professional & scientific | 2026 |
| Melanin Trader Ltd | Arts & recreation | 2025 |
| Mellish Investments Limited | Real estate | 2022 |
| Mellish Road Residents Association Limited | Households | 2004 |
| Melodi Cleaning Services Ltd | Administrative & support | 2025 |
| Melody Healthcare (Holdings) Limited | Financial services | 2022 |
| Melody Healthcare Limited | Wholesale & retail | 2003 |
| Melrose CS Ltd | Administrative & support | 2019 |
| Mels Blooms and Balloons Ltd | Wholesale & retail | 2025 |
| Melts My Heart Ltd | Manufacturing | 2025 |
| Memora Haven Ltd | Wholesale & retail | 2025 |
| Memorabilia 4 U Ltd | Wholesale & retail | 2026 |
| Memorial Services (Midlands) Ltd | Other services | 2011 |
| Memphis Belle (Midlands) Ltd | Real estate | 2025 |
| Mems Engineering Solutions Ltd | Professional & scientific | 2025 |
| Menceneo Ltd | Wholesale & retail | 2024 |
| Mental Wealth Community CIC | Education | 2026 |
| MEO Studio Limited | Professional & scientific | 2024 |
| Meraki Visuals Ltd | Information & communication | 2025 |
| Mercia Golf Ltd | Wholesale & retail | 2022 |
| Mercia Swim School Ltd | Arts & recreation | 2024 |
| Mercian Accounting Solutions Ltd. | Professional & scientific | 2010 |
| Mercian Weldcraft Trustees Limited | Other services | 2025 |
| Mercox Ltd | Education | 2026 |
| Mercymos Healthcare Limited | Health & social care | 2022 |
| Mereshire Developments Limited | Administrative & support | 1987 |
| Meridian FP Ltd | Financial services | 2021 |
| Meridian Wharf Ltd | Construction | 2026 |
| Merricks Transport Services Ltd | Professional & scientific | 2026 |
| Merwips Limited | Health & social care | 2023 |
| MES Health and Safety Consulting Ltd | Professional & scientific | 2021 |
| Met-Sort (Cheslyn HAY) Limited | Wholesale & retail | 1997 |
| Met-Sort (Recycling) Limited | Water & waste | 2008 |
| Meta Physiotherapy & Performance Ltd | Health & social care | 2023 |