| Malvern Leisure Homes and Vehicles Ltd | Wholesale & retail | 2025 |
| Malvern Tyres (Wholesale) Limited | Wholesale & retail | 2000 |
| Malvern Tyres Group Limited | Professional & scientific | 2016 |
| Malvern Tyres Holdings Limited | Financial services | 2008 |
| Malvern Tyres Limited | Professional & scientific | 2002 |
| MAM Motors Limited | Wholesale & retail | 2023 |
| Mamachelo Ltd | Hospitality | 2023 |
| Mammal Society(The) | Professional & scientific | 1979 |
| Mamo Organics Ltd | Hospitality | 2025 |
| Manacel IT Services Ltd | Information & communication | 2022 |
| Manavalan’S Ltd | Construction | 2018 |
| Manchester Working Limited | Construction | 2006 |
| Mandair Group Limited | Transport & logistics | 2023 |
| Mandala Estates Limited | Real estate | 2025 |
| Mandbheatingsolutions Ltd | Construction | 2021 |
| Mander HR Ltd | Professional & scientific | 2012 |
| Mandy Goddings Theatre Arts Ltd | Education | 2008 |
| Mandy Norman Limited | Financial services | 2011 |
| Mani&Ross Ltd | Health & social care | 2026 |
| Manifest Design Workshop Ltd | Construction | 2016 |
| Mann Builders Ltd | Construction | 2020 |
| Mann Made Ltd | Manufacturing | 2023 |
| Manners Construction & Landscaping Services Limited | Construction | 2023 |
| Manor Barn Maintenance Limited | Construction | 2025 |
| Manor Court Limited | Information & communication | 2005 |
| Manor Farm FUN Ltd | Health & social care | 2023 |
| Manor Health Limited | Health & social care | 2006 |
| Manor Wellness Ltd | Health & social care | 2025 |
| Manor Windows Ltd | Manufacturing | 2020 |
| Manylion Construction Limited | Construction | 2014 |
| MAP Software Solutions Ltd | Information & communication | 2023 |
| Maplan UK Limited | Administrative & support | 2003 |
| Maple (124) Limited | Households | 1997 |
| Maple (237) Limited | Households | 2004 |
| Maple (239) Limited | Households | 2004 |
| Maple (250) Limited | Households | 2005 |
| Maple (26) Limited | Households | 1991 |
| Maple (314) Limited | Households | 2007 |
| Maple (322) Limited | Households | 2007 |
| Maple (323) Limited | Households | 2007 |
| Maple (347) Limited | Households | 2008 |
| Maple (370) Limited | Households | 2012 |
| Maple (413) Limited | Households | 2016 |
| Maple (438) Limited | Households | 2018 |
| Maple (458) Limited | Households | 2019 |
| Maple (472) Limited | Households | 2021 |
| Maple Tree Developments Ltd | Construction | 2018 |
| MAPP76 Ltd | Transport & logistics | 2016 |
| Marble Holdings UK Limited | Energy | 2015 |
| Marble Power Limited | Energy | 2013 |
| Marble Power Trading Ltd | Energy | 2018 |
| Marc Said Ltd | Professional & scientific | 2007 |
| Marchwood Flat Management Limited | Households | 1991 |
| Marcus Hannaford Fencing | | 1998 |
| Marday Ltd | Hospitality | 2024 |
| Mare Street Projects Limited | Hospitality | 2016 |
| Marea Services Ltd | Information & communication | 2025 |
| Margot Jakobson Visuals Ltd | Professional & scientific | 2026 |
| Maria DI Michele Ltd | Extraterritorial | 2025 |
| Marina Coral Homeware Ltd | Wholesale & retail | 2021 |
| Mario Driving Ltd | Transport & logistics | 2019 |
| Marisal Ltd | Hospitality | 2024 |
| Marit Venture Limited | Hospitality | 2024 |
| Mark Blake Limited | Other services | 2016 |
| Mark Blake Media Ltd | Information & communication | 2026 |
| Mark Blake Trichology Limited | Health & social care | 2014 |
| Mark Brooks Education Limited | Professional & scientific | 2010 |
| Mark Harmer Eyecare Limited | Health & social care | 2019 |
| Mark Harwood the Health & Wellbeing Coach Ltd | Professional & scientific | 2024 |
| Mark Wadmore Mortgages Ltd | Financial services | 2016 |
| Market Drayton Dental Practice Limited | Health & social care | 2021 |
| Market Stall Takeaway Food Co. LLP | | 2025 |
| Market Trend Ltd | Information & communication | 2004 |
| Marketing Punch Ltd | Administrative & support | 2008 |
| Markey Building Services Limited | Construction | 2013 |
| Markey Construction Limited | Construction | 2015 |
| Markey Developments LLP | | 2004 |
| Markey Electrical Solutions Ltd | Construction | 2023 |
| Markey Investment Holdings Ltd | Financial services | 2020 |
| Markey Ross Developments Limited | Construction | 2015 |
| Markey Student Property Limited | Hospitality | 2003 |
| Markjbuckley Limited | Construction | 2015 |
| Marl Bank Management Association Limited | Households | 1979 |
| Marla Utilities Limited | Information & communication | 2017 |
| Marlborough Charcoal Grill Ltd | Hospitality | 2012 |
| Marlee Installations Ltd | Construction | 2012 |
| Marlie James Counselling Ltd | Health & social care | 2024 |
| Marlings Limited | Manufacturing | 1922 |
| Marmalade Restaurants Limited | Hospitality | 2021 |
| Marmr Properties Ltd | Households | 2021 |
| Marocboyz Ltd | Wholesale & retail | 2025 |
| Marram Commerce Limited | Wholesale & retail | 2026 |
| Mars Lettings Ltd | Real estate | 2019 |
| Mars Maintenance Limited | Manufacturing | 2013 |
| Mars Valve UK Limited | Wholesale & retail | 2000 |
| Marsh Court Farm Limited | Agriculture & fishing | 1999 |
| Marshall Langston Limited | Manufacturing | 1966 |
| Marshall Mechanical Engineering Ltd | Manufacturing | 2014 |
| Marshalling CTE CIC | Education | 2025 |
| Marshalls Driveways & Sons Limited | Construction | 2018 |