| Mancbuses Limited | Wholesale & retail | 2020 |
| Manchester Building Design Ltd | Professional & scientific | 2020 |
| Manchester Car Hire Limited | Extraterritorial | 1986 |
| Manchester Film Festival Limited | Administrative & support | 2015 |
| Manchester Gaming Company Limited | Administrative & support | 2015 |
| Manchester GAS Ltd | Construction | 2018 |
| Manchester Landscaping NW Ltd | Administrative & support | 2026 |
| Manchester Maintenance Services Limited | Other services | 2020 |
| Manchester Paving & Roofing Limited | Construction | 2024 |
| Manchester Physiotherapy Clinic Limited | Health & social care | 2015 |
| Manchester Property Solutions Limited | Real estate | 2016 |
| Manchester Sash Window Company Ltd | Construction | 2025 |
| Manchester Trailers Limited | Manufacturing | 2021 |
| Manchester Van Hire Limited | Transport & logistics | 1983 |
| Manchesterlanddrainage Ltd | Administrative & support | 2025 |
| Manchestertravelandtours Ltd | Administrative & support | 2026 |
| Mancunian Spring Company Limited | Manufacturing | 2023 |
| Manoranjan CIC | Information & communication | 2020 |
| MAP Air Conditioning Ltd | Construction | 2013 |
| Maple House Properties Ltd. | Households | 2010 |
| Marie Margaret Limited | Real estate | 2015 |
| Mark Lyons Recruitment Limited | Administrative & support | 2020 |
| Marketaylor Limited | Professional & scientific | 2017 |
| Marketaylor Property Limited | Real estate | 2019 |
| Marl Chapel Holdings Ltd | Real estate | 2020 |
| Marrkz Limited | Wholesale & retail | 2020 |
| Mars Project Design Ltd | Professional & scientific | 2014 |
| Marshall Auto Park Ltd | Wholesale & retail | 2026 |
| Martha Limited | Health & social care | 2014 |
| Martin Ingham Limited | Extraterritorial | 1999 |
| Martina Holdings Limited | Manufacturing | 2024 |
| Masmo Capital Ltd | Real estate | 2025 |
| Masons Consulting Limited | Information & communication | 2022 |
| Mass Design Limited | Professional & scientific | 2020 |
| Maths & More Limited | Education | 2014 |
| Matley Honey Co Ltd | Agriculture & fishing | 2025 |
| Matley Software Limited | Information & communication | 2002 |
| Matt Gilks Goalkeeping Ltd | Education | 2025 |
| Mattal Building Services Limited | Professional & scientific | 2021 |
| Matthew Baqueriza-Jackson Ltd | Administrative & support | 2019 |
| Matthew Clarke Contracting Ltd | Professional & scientific | 2018 |
| Matthew Hibbert Ltd | Wholesale & retail | 2023 |
| Maxima Lead Generation Ltd | Wholesale & retail | 2019 |
| Maxx Haulage Limited | Transport & logistics | 2017 |
| Mayco Holdings Ltd | Financial services | 2025 |
| Mayfair Minibuses Limited | Transport & logistics | 2006 |
| MB Life Solutions Ltd | Education | 2022 |
| MB Symbioconsul Limited | Professional & scientific | 2019 |
| MB Transport MCR Ltd | Transport & logistics | 2025 |
| MBS Kitchen and Design Ltd | Construction | 2026 |
| MCC - Mark Calvert Construction Ltd | Construction | 2020 |
| Mccormack Estates Ltd | Real estate | 2013 |
| Mchd Properties Limited | Real estate | 2015 |
| Mcilroy Holdings Limited | Professional & scientific | 2018 |
| Mckay Homes Limited | Construction | 2000 |
| Mckc Roofing Ltd | Construction | 2025 |
| Mcmark Detailing Manchester Ltd | Administrative & support | 2026 |
| MCR Agnc Ltd | Wholesale & retail | 2020 |
| MCR Partnership Ltd | Financial services | 2025 |
| Mead in Manchester Ltd | Manufacturing | 2025 |
| Meadow Blinds Limited | Wholesale & retail | 2012 |
| Mears Materials Handling Limited | Manufacturing | 2019 |
| Mechanical Fitting Services Ltd | Manufacturing | 2024 |
| Medisense Ltd | Health & social care | 2026 |
| Mediskills Health & Safety Consulting Limited | Professional & scientific | 2024 |
| Megafan Technologies Limited | Manufacturing | 2006 |
| Melectrical N/W Limited | Construction | 2015 |
| Melia Property Ltd | Real estate | 2026 |
| Mellon Estates Ltd | Real estate | 2022 |
| Mellon Limited | Real estate | 2018 |
| Meltham Grange Farm Ltd | Hospitality | 2020 |
| Meredith & Eyre Holdings Limited | Financial services | 2020 |
| Meredith and Eyre Limited | Manufacturing | 1956 |
| Merel Pharma Limited | Professional & scientific | 2024 |
| Meridian Asset Placement Limited | Administrative & support | 2004 |
| Meridian Transfers Ltd | Transport & logistics | 2026 |
| Meridian Vehicle Sales Limited | Wholesale & retail | 2003 |
| Merlewood Properties Limited | Construction | 2021 |
| MF9 Limited | Wholesale & retail | 2022 |
| MG Properties NW Ltd | Real estate | 2025 |
| Mghj Holdings Limited | Wholesale & retail | 2016 |
| MGN Business Limited | Professional & scientific | 2012 |
| MGN Projects Limited | Construction | 2018 |
| MH Business Support Limited | Administrative & support | 2019 |
| MIA Fabrics Limited | Administrative & support | 2021 |
| Miahct Ltd | Administrative & support | 2020 |
| Micro Design Solutions Ltd | Information & communication | 2012 |
| MIH Medical Solutions Limited | Health & social care | 2024 |
| Milena Design Ltd | Manufacturing | 2015 |
| Military KIT Limited | Administrative & support | 2017 |
| Millennium Medical Products Limited | Manufacturing | 1997 |
| Mils Processes Limited | Professional & scientific | 2009 |
| Mintelec Limited | Construction | 2015 |
| Minton Properties Ltd | Real estate | 2026 |
| Miracle Mart Limited | Wholesale & retail | 2025 |
| Miraz Transport Ltd | Transport & logistics | 2025 |
| MJD Heating Limited | Construction | 2020 |
| MJK Motors Ltd | Wholesale & retail | 2025 |
| MJP Design Ltd | Administrative & support | 2007 |
| MJR Group Ltd | Wholesale & retail | 2023 |