| M J B GAS and Plumbing Ltd | Construction | 2021 |
| M M J Investments Ltd | Administrative & support | 2007 |
| M N Badger Ltd | Construction | 2011 |
| M Talent Management Ltd | Professional & scientific | 2015 |
| M Waldron Music Limited | Professional & scientific | 2013 |
| M&C Property Service Ltd | Administrative & support | 2014 |
| M&Lk Communications Ltd | Information & communication | 2012 |
| M&M Tasty Food Company Ltd | Hospitality | 2022 |
| M&O Developments Ltd | Construction | 2019 |
| M&O Medicals Ltd | Health & social care | 2026 |
| M-Tech Electrical Contractors Limited | Construction | 2009 |
| M.B.J.C. Limited | Administrative & support | 2013 |
| M.B.M. Professional Services Ltd | Professional & scientific | 2003 |
| M.I.A. Skin Therapy Ltd | Wholesale & retail | 2021 |
| M.I.C.A. Direct Ltd | Construction | 2017 |
| M3 Food Ltd | Wholesale & retail | 2023 |
| M33 Autoparts Ltd | Wholesale & retail | 2023 |
| M33 Group Holdings Limited | Professional & scientific | 2026 |
| M33 Property Holdings Limited | Real estate | 2023 |
| M6 Investment Group Limited | Real estate | 2025 |
| M60 Modified Ltd | Administrative & support | 2026 |
| M60 Windscreens Ltd | Wholesale & retail | 2024 |
| Mableeds Ltd | Real estate | 2018 |
| Mablo Electrical Limited | Construction | 2026 |
| MAC and Melt Ltd | Hospitality | 2025 |
| Mackstock Leisure Limited | Hospitality | 2020 |
| Macleod Accounting Limited | Professional & scientific | 2014 |
| Macleodbradley Limited | Other services | 2010 |
| Macrane Developments Limited | Real estate | 2024 |
| Macrane Projects Limited | Construction | 2023 |
| MAD Wholesale Limited | Wholesale & retail | 2023 |
| Maddens Limited | Wholesale & retail | 2006 |
| Made by Animation Limited | Professional & scientific | 2019 |
| Made by Other Ltd | Professional & scientific | 2024 |
| MAE HAN Ltd | Hospitality | 2025 |
| Magc Limited | Real estate | 2012 |
| Maggie Finn's Limited | Wholesale & retail | 2014 |
| Maggie Kufeldt Ltd | Professional & scientific | 2018 |
| Magic Smart Tattoo Ltd | Arts & recreation | 2019 |
| Maha Properties Ltd | Real estate | 2018 |
| Mahin Consulting Limited | Information & communication | 2014 |
| Maid Marian House Ltd | Construction | 2015 |
| Maid Marian House Management (Notts) Ltd | Real estate | 2019 |
| MAID2CLEAN Wilmslow Ltd | Administrative & support | 2017 |
| Main Accountants Ltd | Professional & scientific | 2023 |
| Maine Projects Ltd | Construction | 2012 |
| Maineeco Ltd | Information & communication | 2022 |
| Maison Build (NW) Ltd | Construction | 2014 |
| Maitland SA Limited | Real estate | 2023 |
| Majd Limited | Real estate | 2014 |
| Major Financial Services Ltd | Financial services | 2025 |
| Make My Space Ltd | Construction | 2020 |
| Makers Retail Limited | Wholesale & retail | 2019 |
| Making Futures CIC | Wholesale & retail | 2020 |
| Malabar-Properties UK Ltd | Real estate | 2025 |
| Mallya Medical Services Limited | Health & social care | 2013 |
| Malt House Management Newlyn Limited | Households | 2011 |
| Mama Kitchen Foods Ltd | Hospitality | 2026 |
| Mamma G'S Ltd | Hospitality | 2021 |
| MAN of GOD Limited | Wholesale & retail | 2025 |
| Management and Strategies Limited | Financial services | 2007 |
| Managemybills.Com Limited | Financial services | 2020 |
| Manasa VEG and Vegan Limited | Hospitality | 2024 |
| Manc Global Logistics Ltd | Transport & logistics | 2019 |
| Manc Group Ltd | Wholesale & retail | 2017 |
| Manchester 33 Limited | Professional & scientific | 2019 |
| Manchester Academy of Traditional Chinese Medicine Limited | Education | 2016 |
| Manchester Action for Children | Other services | 2008 |
| Manchester Advanced Dentistry Ltd | Health & social care | 2024 |
| Manchester Antique Company Limited | Wholesale & retail | 2005 |
| Manchester BAG Company Ltd | Wholesale & retail | 2026 |
| Manchester BEE Sock Company Ltd | Other services | 2018 |
| Manchester Boilers Ltd | Construction | 2025 |
| Manchester Cooling & Refrigeration Ltd | Construction | 2020 |
| Manchester Financial Services Limited | Financial services | 2002 |
| Manchester Fireworks Limited | Wholesale & retail | 2017 |
| Manchester Friends Properties Ltd | Households | 2022 |
| Manchester Glassworks Ltd | Manufacturing | 2021 |
| Manchester Heating Ltd | Manufacturing | 2012 |
| Manchester Honey Company Ltd | Agriculture & fishing | 2021 |
| Manchester Housing Developments Ltd | Real estate | 2021 |
| Manchester Housing Group Limited | Real estate | 2014 |
| Manchester Pipe and Site Services Limited | Construction | 2019 |
| Manchester Plant Services Ltd | Other services | 2015 |
| Manchester Plumbing Services Ltd | Construction | 2020 |
| Manchester Power Limited | Professional & scientific | 2003 |
| Manchester Prime Ltd | Wholesale & retail | 2025 |
| Manchester Printers Group Limited | Information & communication | 2013 |
| Manchester Printers Ltd | Information & communication | 2012 |
| Manchester Short Shorts Limited | Wholesale & retail | 2021 |
| Manchester Urban Finance Corporation (EOT) Limited | Financial services | 2025 |
| Manchester Urban Finance Corporation Limited | Professional & scientific | 1995 |
| Mancmade Productions Limited | Information & communication | 2020 |
| Mandolin Business Services Ltd | Professional & scientific | 2022 |
| Mandy Jane Promotions Ltd | Administrative & support | 2005 |
| Mane Estates Ltd | Real estate | 2020 |
| Mangiando Calabro Ltd | Hospitality | 2019 |
| Manpen Systems Limited | | 1966 |
| Mansuroglu Limited | Manufacturing | 2019 |
| Mantre Limited | Professional & scientific | 2025 |