| MDT Trade Windows and Doors Limited | Administrative & support | 2023 |
| MDT Trade Windows Limited | Manufacturing | 2008 |
| MDV Solutions Limited | Professional & scientific | 2025 |
| ME & YOU Properties Limited | Real estate | 2023 |
| ME and My Glass Ltd | Wholesale & retail | 2022 |
| ME Therapy Ltd | Other services | 2024 |
| Mead Financial Planning Limited | Financial services | 2005 |
| Meadcourt Limited | Real estate | 1989 |
| Meaden Property Developments Ltd | Construction | 2021 |
| Meaden Services (UK) Ltd | Information & communication | 2011 |
| Meadow Lane Holdings Limited | Professional & scientific | 2008 |
| Meadow Lane Industrial Estate Limited | Real estate | 2003 |
| Meadow Lane Investments Limited | Real estate | 1963 |
| Meadow Oak Limited | Manufacturing | 2022 |
| Meadow Tree Homes Ltd | Construction | 2024 |
| Meadow View Estate (Management Company) Limited | Real estate | 2013 |
| Meadowbrook Motors Limited | Wholesale & retail | 2016 |
| Meadowhall South Ltd | Construction | 2023 |
| Meadowmead Property Ltd | Administrative & support | 2010 |
| Meadowoak Developments Limited | Construction | 2019 |
| Meadowpark Properties Limited | Real estate | 2024 |
| Meadows Advice Group | Health & social care | 1991 |
| Meadows Barber Diari Ltd | Other services | 2022 |
| Meadows Community Childcare Group CIC | Health & social care | 2025 |
| Meadows Halal Food Store Ltd | Wholesale & retail | 2025 |
| Meadows Ozone Energy Services Limited | Professional & scientific | 2009 |
| Meadows Play Centre Ltd | Arts & recreation | 2025 |
| Meadows Together Youth and Community | Health & social care | 2025 |
| MEADOWS18 Limited | Other services | 2025 |
| Meadwell Plumbing & Heating Ltd | Construction | 2012 |
| Meal Maker Limited | Hospitality | 2019 |
| Meal Movers Ltd | Hospitality | 2025 |
| Mearl Consultancy Limited | Professional & scientific | 2019 |
| Mearm Limited | Education | 2014 |
| Mears & Cotterill Limited | Extraterritorial | 2002 |
| Measure for Measure Ltd | Professional & scientific | 2004 |
| Measures and Company Limited | Professional & scientific | 2012 |
| Meat 4 U Butchers Ltd | Wholesale & retail | 2024 |
| Meat Trade Centre Ltd | Manufacturing | 2018 |
| MEB Power Limited | Energy | 2016 |
| Mebs Facilities Management Limited | Construction | 2026 |
| Mebs Fire and Security Limited | Construction | 2026 |
| Mebs Group Limited | Construction | 2024 |
| Mebs Renewables Limited | Construction | 2026 |
| Mecauto UK Ltd | Wholesale & retail | 2026 |
| Mech-Elec Building Services Limited | Construction | 2023 |
| Mechanic Match Ltd | Wholesale & retail | 2026 |
| Mechanical Validation Services Ltd | Professional & scientific | 2021 |
| Mechanicco Ltd | Wholesale & retail | 2019 |
| Mechanofix 24 Limited | Manufacturing | 2020 |
| Mecra Ltd | Hospitality | 2022 |
| Mecsa & Associates Limited | Health & social care | 2014 |
| MED 2 MED Ltd | Health & social care | 2021 |
| MED MIS Consultancy Limited | Education | 2018 |
| MED Software Limited | Extraterritorial | 2015 |
| MED XB Limited | Financial services | 2022 |
| Medaix Limited | Information & communication | 2024 |
| Medaxis Limited | Professional & scientific | 2026 |
| Medcare Group Ltd | Administrative & support | 2023 |
| Medchem Pharma Ltd | Health & social care | 2024 |
| Medclinic Ltd | Other services | 2008 |
| Medex Limited | Wholesale & retail | 2021 |
| Medexop Limited | Wholesale & retail | 2023 |
| Medi Locum Limited | Health & social care | 2009 |
| Medi Support Ltd | Health & social care | 2024 |
| Medi-Direct International Limited | Extraterritorial | 2000 |
| Media First Limited | Administrative & support | 1984 |
| Media HUT (GB) Ltd. | Manufacturing | 2014 |
| Media Mace Ltd | Information & communication | 2024 |
| Media Maker Ltd. | Information & communication | 1992 |
| Media Manners Ltd | Professional & scientific | 2022 |
| Media Morgan Limited | Information & communication | 2023 |
| Media Robots Ltd | Information & communication | 2026 |
| Media Tech Solutions Ltd | Information & communication | 2020 |
| Media Toolbox Ltd | Information & communication | 2018 |
| MEDIA27 Ltd | Information & communication | 1996 |
| Mediaconsult Ltd | Professional & scientific | 2026 |
| Mediawall Co Limited | Construction | 2026 |
| Medic Green Limited | Health & social care | 2021 |
| Medica Investments Ltd | Real estate | 2021 |
| Medical Advice Today Ltd | Information & communication | 2024 |
| Medical and Retail Systems Ltd | Information & communication | 2021 |
| Medical Elite Ltd | Real estate | 2020 |
| Medical Indicators Europe Ltd | Wholesale & retail | 1988 |
| Medical Makeover Limited | Health & social care | 2025 |
| Medical Marketing Ltd | Wholesale & retail | 2022 |
| Medical Reports Ltd | Professional & scientific | 2020 |
| Medical Studio Ltd | Health & social care | 2023 |
| Medical Supply Management Ltd | Water & waste | 2023 |
| Medical Ultrasonics Ltd | Health & social care | 2025 |
| Medical Wealthcare Limited | Financial services | 2007 |
| Medical Wealthcare Planning Limited | Financial services | 2002 |
| Medicalbrainbox Ltd | Professional & scientific | 2015 |
| Medicina Pharma Limited | Wholesale & retail | 2023 |
| Medicine Box (Investment) Ltd | Real estate | 2020 |
| Medicine Box (Nottingham) Limited | Wholesale & retail | 2019 |
| Medicine Ventures Limited | Wholesale & retail | 2019 |
| Medicounts Limited | Professional & scientific | 2014 |
| Medics on 2 Limited | Health & social care | 2025 |
| Medics Paradigm Ltd | Health & social care | 2015 |