| M & a Commercials Ltd | Wholesale & retail | 2019 |
| M & J K Limited | Administrative & support | 2021 |
| M & S Stores 2 Ltd | Wholesale & retail | 2019 |
| M & S Stores Limited | Wholesale & retail | 2003 |
| M & T Construction Services N/W Ltd | Construction | 2025 |
| M B Services North West Limited | Other services | 2017 |
| M Doyle Roofing Ltd | Construction | 2026 |
| M F Logistics (UK) Limited | Administrative & support | 2002 |
| M Grehan Plumbing & Heating Limited | Construction | 2012 |
| M H a Integrated Electronic Services Limited | Information & communication | 1998 |
| M P Construction N W Limited | Construction | 2016 |
| M&F Carpets & Flooring Ltd | Wholesale & retail | 2025 |
| M&H Japanese Motors Ltd | Wholesale & retail | 2026 |
| M-Y Groundworks & Paving Ltd | Construction | 2011 |
| M.W. Motors Ltd | Wholesale & retail | 2019 |
| M2DR Limited | Construction | 2025 |
| Machen and Company Limited | Hospitality | 2010 |
| Machine Technologies Limited | Manufacturing | 2014 |
| Machines and Tools Limited | Manufacturing | 2003 |
| Macrotek Material Solutions Ltd | Manufacturing | 2026 |
| Macs Auto Detailing Supplies Limited | Wholesale & retail | 2019 |
| Macs Demolition Services Limited | Construction | 2011 |
| Macs Digger Services Limited | Mining & quarrying | 2025 |
| Made in Leigh Limited | Information & communication | 2022 |
| Made in Poland Ltd | Manufacturing | 2017 |
| MAG Interior&Decorating Ltd | Construction | 2024 |
| Magnet Store Ltd | Wholesale & retail | 2017 |
| Magnum Furniture Store Limited | Wholesale & retail | 2009 |
| Majestic Doors & More Limited | Wholesale & retail | 2022 |
| Making Memories Childcare Recruitment Ltd | Administrative & support | 2017 |
| Mallett & Winstanley Limited | Wholesale & retail | 2019 |
| Malrow Ltd | Real estate | 2026 |
| Mama Vicky Catering Ltd | Hospitality | 2026 |
| MAN & Car UK Logistics Ltd | Transport & logistics | 2018 |
| Manchester Auto Spa Ltd | Administrative & support | 2026 |
| Manchester Connect Ltd | Real estate | 2019 |
| Manchester Property Photography Ltd | Professional & scientific | 2026 |
| Mandarin 888 Ltd | Hospitality | 2026 |
| Manleigh CIC | Health & social care | 2022 |
| Mano Thomas Ltd | Health & social care | 2014 |
| Manor Consulting NW Limited | Construction | 2022 |
| Manor Hire Marquees Limited | Other services | 1997 |
| Manshaah Estate Limited | Real estate | 2022 |
| Mansprop Ltd | Real estate | 2023 |
| Manta Design Studio Ltd | Professional & scientific | 2023 |
| Manyashil International Ltd | Wholesale & retail | 2021 |
| Marina GAS Ltd | Construction | 2013 |
| Market Street Discount Store Ltd | Administrative & support | 2016 |
| Marona Signature Ltd | Wholesale & retail | 2026 |
| Marquee Party Ltd | Administrative & support | 2023 |
| Marstrut Limited | Construction | 1997 |
| Masan Ltd | Real estate | 2021 |
| Masri Holdings Limited | Information & communication | 2025 |
| Masser Properties Limited | Real estate | 2021 |
| Mastiff Distribution Ltd | Wholesale & retail | 2023 |
| Matcha Dating Limited | Administrative & support | 2026 |
| Matterial Ltd | Wholesale & retail | 2025 |
| MAV Accounting Ltd | Professional & scientific | 2021 |
| Maximillians Leigh Limited | Hospitality | 2019 |
| MAY Technical Advisory Services Ltd | Professional & scientific | 2026 |
| Mayo Consulting Limited | Professional & scientific | 2008 |
| Mayo Professional Training Ltd. | Administrative & support | 2007 |
| MB Windows & Conservatories Limited | Construction | 2010 |
| MBA Driveways Ltd | Administrative & support | 2023 |
| Mbsi Detailing Limited | Professional & scientific | 2007 |
| Mccready Property Group Ltd | Real estate | 2026 |
| Mcodus Ltd | Health & social care | 2025 |
| Meadow Management Company (Hatfield) Limited | Households | 2021 |
| Media Tech Information Ltd | Wholesale & retail | 2022 |
| Mega Property & Management Limited | Real estate | 2020 |
| Mega Services (UK) Limited | Administrative & support | 2008 |
| Megan Lloyd Bridal Ltd | Other services | 2026 |
| Megan.R.S Ltd | Wholesale & retail | 2025 |
| Megosome Ltd | Other services | 2025 |
| Melt Town Ltd | Hospitality | 2025 |
| Mendes Building Solutions Limited | Construction | 2021 |
| Mental Edge Ltd | Wholesale & retail | 2023 |
| Merinal Ltd | Wholesale & retail | 2008 |
| Metaverse Services Ltd | Administrative & support | 2024 |
| MGM Auto's Limited | Wholesale & retail | 2011 |
| MH Skyrise UK Limited | Wholesale & retail | 2026 |
| MHK Sales Ltd | Wholesale & retail | 2023 |
| MHR Technology Consultancy Ltd | Manufacturing | 2026 |
| MIA Motor Group Limited | Wholesale & retail | 2026 |
| Miacali Ltd | Transport & logistics | 2025 |
| Mican Plastering Limited | Construction | 2003 |
| Micha Construction Ltd | Construction | 2016 |
| Michael John Ashcroft Fine Art Limited | Arts & recreation | 2014 |
| Michael Thorpe Services Limited | Transport & logistics | 2017 |
| Michal Raciborski Ltd | Transport & logistics | 2019 |
| Mida's Touch Beauty Supplies Ltd | Wholesale & retail | 2020 |
| Midas Global Solutions Limited | Professional & scientific | 2026 |
| Mihai Ciobotaru Transport Ltd | Transport & logistics | 2021 |
| Mike Ince Car Sales Limited | Wholesale & retail | 2018 |
| Mil-Link Ltd | Information & communication | 2023 |
| Mili Investments Ltd | Real estate | 2021 |
| Millennium Storage & Interiors Ltd. | Professional & scientific | 1998 |
| Millennium Storage Installations Limited | Construction | 1998 |
| Millrose Group Holdings Limited | Financial services | 2024 |
| Milly Properties Ltd | Real estate | 2023 |