| Mafd Cloud Services Limited | Information & communication | 2019 |
| Mafura Actuarial Consulting Limited | Professional & scientific | 2025 |
| MAG45 (UK) Limited | Wholesale & retail | 2000 |
| Magena Technologies Limited | Administrative & support | 2014 |
| Magenta Corporate Ltd | Hospitality | 2019 |
| Magic Detail Limited | Wholesale & retail | 2021 |
| Magna Paper Ltd | Administrative & support | 2020 |
| Magnifi Advisory Limited | Information & communication | 2024 |
| Magnifisun Limited | Real estate | 2026 |
| Magnify Digital Limited | Professional & scientific | 2021 |
| Magnitude Quantity Surveyors Ltd | Professional & scientific | 2019 |
| Magnolia Blooms UK Ltd | Wholesale & retail | 2023 |
| Magnolia Blossom LP | | 2020 |
| Magnolia Leaf Nominee Limited | Financial services | 2020 |
| Magnolia Tree GP Limited | Financial services | 2020 |
| Magu Manchester Limited | Hospitality | 2019 |
| Maguire Family Law Holdings Limited | Financial services | 2023 |
| Maguire Family Law Limited | Professional & scientific | 2017 |
| Magus Consultants Private Limited | Information & communication | 2014 |
| Maha Consultancy Limited | Health & social care | 2022 |
| Mahalaxmi Investments Limited | Real estate | 2021 |
| Maias Group Ltd | Arts & recreation | 2017 |
| Maid in Comfort Limited | Administrative & support | 2023 |
| Maid in the Cotswolds Ltd | Administrative & support | 2012 |
| Maid Marian House Management Ltd | Real estate | 2016 |
| Maids of Cheshire Limited | Administrative & support | 2025 |
| Main Stream Music Ltd | Information & communication | 2018 |
| Mainstay Associates Ltd | Extraterritorial | 2021 |
| Maintex Landscape and Gardening Ltd | Administrative & support | 2026 |
| Maintex Property Maintenance Ltd | Construction | 2026 |
| Maison DE Jardin Limited | Construction | 2025 |
| Maison Kongo Ltd | Wholesale & retail | 2026 |
| Maison Vitalite Limited | Arts & recreation | 2025 |
| Maison YS Limited | Real estate | 2025 |
| Majestic Publications Limited | Information & communication | 2002 |
| Majoor Limited | Professional & scientific | 2014 |
| MAK Connect Limited | Health & social care | 2021 |
| Make & Build Partnerships Limited | Construction | 2025 |
| Make Money Limited | Professional & scientific | 2006 |
| Make Space Landscape Architecture Limited | Professional & scientific | 2022 |
| Make US a Brew Ltd | Arts & recreation | 2004 |
| Maker Academy Ltd | Professional & scientific | 2025 |
| Makin Studios Ltd | Professional & scientific | 2021 |
| Maks Retailing Ltd | Wholesale & retail | 2016 |
| MAL Investments Ltd | Real estate | 2021 |
| Malahat Properties Limited | Construction | 2006 |
| Malarstrand Ltd | Professional & scientific | 2024 |
| Malcolm Taylor (Commercials) Ltd | Wholesale & retail | 1978 |
| Malcolm Walsh Limited | Transport & logistics | 2006 |
| Malmesbury Medical Enterprise Limited | Administrative & support | 2004 |
| Malmo Holdings Ltd | Financial services | 2024 |
| Malolo Ltd | Agriculture & fishing | 2015 |
| Malone Consultancy Services Limited | Professional & scientific | 2017 |
| Maloney Homes Ltd | Real estate | 2024 |
| Malrae Residents Company Limited | Households | 1999 |
| Malren IT Limited | Information & communication | 2022 |
| Malta AE Holding (UK) Ltd | Extraterritorial | 2012 |
| Maluk Ltd | Other services | 2026 |
| Malvern HE Partnerships Limited | Education | 2024 |
| Malvern House Group Limited | Professional & scientific | 1999 |
| Malvern House International Limited | Education | 1999 |
| Malvern International PLC | Education | 2004 |
| Malynn Limited | Administrative & support | 2016 |
| MAM 32 Limited | Financial services | 2015 |
| Mama and Mimi Limited | Wholesale & retail | 2019 |
| Mama MIO Distribution Limited | Manufacturing | 2011 |
| Mama MIO Limited | Wholesale & retail | 2004 |
| Mamad Home Ltd | Construction | 2020 |
| Mamucium Aero Limited | Professional & scientific | 2026 |
| Mana Advisory Ltd | Professional & scientific | 2020 |
| Managed Commercial Services Limited | Real estate | 2016 |
| Managed Medical Limited | Administrative & support | 2022 |
| Management Systems Certification Limited | Administrative & support | 2014 |
| Management Tests & Surveys Ltd | Professional & scientific | 1996 |
| Manam Doctors Ltd | Health & social care | 2022 |
| Manchester & Metropolitan Properties Limited | Real estate | 2007 |
| Manchester Airport Taxi Limited | Transport & logistics | 2017 |
| Manchester and Cheshire Foot & Ankle Clinic Ltd | Health & social care | 2012 |
| Manchester Bites Ltd | Administrative & support | 2023 |
| Manchester Breast Cancer Ltd. | Health & social care | 2011 |
| Manchester Breast Oncology Ltd | Health & social care | 2024 |
| Manchester Cake Co Ltd | Manufacturing | 2024 |
| Manchester Central Properties LLP | | 2004 |
| Manchester Collegiate Education Trust | Education | 2011 |
| Manchester Connected Limited | Wholesale & retail | 2020 |
| Manchester Corporate Travel & Logistics Ltd | Transport & logistics | 2025 |
| Manchester Corporate Travel Ltd | Transport & logistics | 2024 |
| Manchester DRY Docks Limited | | 1924 |
| Manchester Endocrinology & Diabetes Limited | Health & social care | 2019 |
| Manchester Endoscopy Ltd | Professional & scientific | 2026 |
| Manchester Engraving Services Ltd | Professional & scientific | 2026 |
| Manchester Glass Properties Ltd | Financial services | 2023 |
| Manchester Harp Festival and Competition Limited | Information & communication | 2025 |
| Manchester Heart Surgery Clinic Ltd | Health & social care | 2024 |
| Manchester HIP and Knee Clinic Limited | Health & social care | 2010 |
| Manchester HIP and Knee Limited | Health & social care | 2011 |
| Manchester HIP Knee Limited | Health & social care | 2020 |
| Manchester Historic Vehicle Club Limited | Administrative & support | 2004 |
| Manchester Hive Ltd | Real estate | 2018 |
| Manchester Industrial Finance Limited | Professional & scientific | 1958 |