| Mapmatic Limited | Construction | 2011 |
| Mapped UP UK - Derby Ltd | Professional & scientific | 2025 |
| Mapperley Kitchen & Bathroom Ltd | Construction | 2024 |
| Maquina Technical Services Ltd | Manufacturing | 2021 |
| Marathon Blinds & Shutters Ltd | Construction | 2011 |
| Marble Hall Little Angels Day Nursery Limited | Education | 2016 |
| Marble Property Services - Land and Development Ltd | Real estate | 2019 |
| Marble Street Limited | Construction | 2020 |
| Marc Pegg Limited | Financial services | 2022 |
| Marcad Engineering Design Ltd | Professional & scientific | 2012 |
| Marcam Consultancy Ltd | Administrative & support | 2018 |
| Marcam Properties Limited | Real estate | 2020 |
| Marcars & Body Repairs Ltd | Wholesale & retail | 2023 |
| March Development Services Limited | Construction | 2019 |
| March Group Holdings Ltd | Financial services | 2021 |
| March Property Developments Limited | Construction | 2019 |
| March Transport Ltd | Transport & logistics | 2017 |
| Marchmont Feltham LLP | | 2017 |
| Marcin Dlugosz Limited | Construction | 2016 |
| Marcin Wilk Ltd | Health & social care | 2018 |
| Marcus J. S. Price Limited | Financial services | 2006 |
| Marcy Homes Limited | Real estate | 2019 |
| Marcy Lettings Ltd | Real estate | 2024 |
| Mardy Promotions Limited | Arts & recreation | 2026 |
| Marght Ltd | Administrative & support | 2025 |
| Margi Rose Ltd | Hospitality | 2023 |
| Marhaul Ltd | Transport & logistics | 2022 |
| Maria Moore Personal Development Limited | Health & social care | 2020 |
| Maria Pizza Limited | Hospitality | 2025 |
| Maria Rafferty Consulting Ltd | Professional & scientific | 2020 |
| Marie Aroma Studio Limited | Manufacturing | 2024 |
| Marie LH Ltd | Real estate | 2025 |
| Marielane Gold Ltd | Hospitality | 2021 |
| Marigolds Cleaning Services Ltd | Administrative & support | 2011 |
| Marin Property Management Ltd | Real estate | 2022 |
| Marine Engineering Solutions Limited | Transport & logistics | 2008 |
| Mario Mini Market Limited | Wholesale & retail | 2025 |
| Mariox Ltd | Transport & logistics | 2017 |
| Mariusz Hernik Ltd | Transport & logistics | 2014 |
| Mariusz Teofilak Ltd | Transport & logistics | 2022 |
| Mark a Webster Building & Conservation Limited | Construction | 2013 |
| Mark Anthony (Construction and Cladding) Limited | Professional & scientific | 2006 |
| Mark Cockerham Civil Engineering Ltd | Construction | 2007 |
| Mark Cotton Engineering Limited | Manufacturing | 2013 |
| Mark Dainty Decorators Limited | Construction | 2006 |
| Mark Dunn Photography Ltd | Professional & scientific | 2024 |
| Mark I Harrison Ltd | Professional & scientific | 2024 |
| Mark K. Williams Limited | Financial services | 2007 |
| Mark KP Trans Ltd | Transport & logistics | 2017 |
| Mark One Engineering Solutions Ltd | Professional & scientific | 2018 |
| Mark Reading Flooring Limited | Construction | 2006 |
| Mark Reynolds Architect Limited | Professional & scientific | 2015 |
| Mark Stuart Properties Ltd | Real estate | 2024 |
| Mark Tassi Ltd | Construction | 2017 |
| Mark Vets Ltd. | Professional & scientific | 2011 |
| Mark Webb Consult Limited | Professional & scientific | 2015 |
| Mark Woodcock Joinery Limited | Construction | 2013 |
| Mark's Motorhomes of Derby Limited | Administrative & support | 2024 |
| Markeaton Fish Bar Ltd | Hospitality | 2016 |
| Markeaton Healthcare Ltd | Wholesale & retail | 2021 |
| Markeaton Stones Barns Management Company Limited | Households | 1996 |
| Markeaton View (Derby) Management Company Limited | Households | 2006 |
| Marked Improvement E-Learning Limited | Information & communication | 2015 |
| Market Colour Technologies Limited | Information & communication | 2024 |
| Market Groszek 4U Ltd | Wholesale & retail | 2020 |
| Market Kubus Ltd | Wholesale & retail | 2020 |
| Marketing Derby Limited | Professional & scientific | 2006 |
| Markham 1 Estates and Lettings Limited | Hospitality | 2023 |
| Markham Global UK Ltd | Construction | 2012 |
| Markip Paint Services Limited | Construction | 2026 |
| Marks & Mason Property Ltd | Real estate | 2023 |
| Marlam Services Limited | Professional & scientific | 2021 |
| Marler Engineering Ltd | Manufacturing | 2023 |
| Marley Logistics Ltd | Transport & logistics | 2019 |
| Marlfield Management Ltd | Extraterritorial | 2018 |
| Marlinspike Residential Limited | Real estate | 2026 |
| Marlix Operations Ltd | Construction | 2020 |
| Marmaris&Barber Limited | Other services | 2026 |
| Maroon (Eco) Ltd | Agriculture & fishing | 2021 |
| Maroon Training Ltd | Education | 2010 |
| Marpal Fire Safety Ltd | Construction | 2022 |
| Marpal Limited | Construction | 1998 |
| Marque Insight Ltd | Administrative & support | 2026 |
| Marquees Plus Ltd | Administrative & support | 2024 |
| Marquis of Ormonde Ltd | Hospitality | 2025 |
| Marquis Property Management Limited | Households | 2024 |
| Marrakesh Derby Ltd | Hospitality | 2020 |
| Marrakesh Investments Ltd | Financial services | 2010 |
| Marresa Ltd | Wholesale & retail | 2011 |
| Marriage-Stanley Ltd | Arts & recreation | 2009 |
| Marron Property Holdings Ltd | Real estate | 2025 |
| Marseille Music Ltd | Arts & recreation | 2024 |
| Marsh Cottage Farm 1964 Limited | Extraterritorial | 2014 |
| Marshall Maintenance Services Ltd | Extraterritorial | 2024 |
| Marshall Mickleover Ltd | Professional & scientific | 2018 |
| Marshall Woodrow Limited | Construction | 2021 |
| Marshridge Limited | Professional & scientific | 2010 |
| Marston Machine Operating Services Limited | Construction | 2025 |
| Martelet Limited | Financial services | 2024 |
| Martin Dalby Limited | Financial services | 2024 |