| Mark Ricketts Consulting Ltd | Administrative & support | 2024 |
| Mark Shardlow Media Limited | Other services | 2017 |
| Mark Short Limited | Construction | 2012 |
| Mark Spencer Consultancy Ltd | Professional & scientific | 2024 |
| Mark Spouge Ltd | Professional & scientific | 2018 |
| Mark Time Care Limited | Health & social care | 2014 |
| Mark Timmins Wealth Management Limited | Financial services | 2009 |
| Mark Wilson Developments Limited | Construction | 2015 |
| Mark-Dum Ltd | Transport & logistics | 2017 |
| MARK1 Lasers Ltd | Professional & scientific | 2020 |
| Markelly Associates Limited | Information & communication | 1999 |
| Markem-Imaje Industries Limited | Manufacturing | 1985 |
| Market Addison Ltd | Wholesale & retail | 2025 |
| Market Chippy Limited | Hospitality | 2019 |
| Market Development Properties UK Limited | Real estate | 2021 |
| Market Development Services Ltd | Other services | 2025 |
| Market Harborough V.E. Limited | Other services | 1999 |
| Market Nexus Limited | Real estate | 1998 |
| Market Overton Industrial Estate Limited | Real estate | 2024 |
| Market Rounds Technologies Ltd. | Information & communication | 2018 |
| Market Square Developments Nottingham Limited | Real estate | 2021 |
| Market Square House Trading Limited | Real estate | 2026 |
| Market View Ltd | Real estate | 2024 |
| Marketboy Ltd | Hospitality | 2020 |
| Marketcheckers Limited | Professional & scientific | 2014 |
| Marketing Cara Company Ltd | Extraterritorial | 2013 |
| Marketing Nottingham and Nottinghamshire Limited | Administrative & support | 1999 |
| Marketmint Ltd | Wholesale & retail | 2025 |
| Markfield Developments Limited | Construction | 2018 |
| Markfield Village Store Ltd | Wholesale & retail | 2019 |
| Markhor Brand Ltd | Wholesale & retail | 2025 |
| Markhor Enterprises Ltd | Manufacturing | 2020 |
| Marklands Build UK Limited | Construction | 2022 |
| Markoval Limited | Administrative & support | 2020 |
| Marks Bars Ltd | Hospitality | 2022 |
| Marks Motor Spares Limited | Wholesale & retail | 2007 |
| Marksd Bees Ltd | Professional & scientific | 2026 |
| Marksman Capital Limited | Construction | 2024 |
| Marksman Investments Limited | Financial services | 2015 |
| Marlborough Hall Ltd | Construction | 2014 |
| Marlborough Hall Management Limited | Real estate | 2018 |
| Marlborough Properties Nottingham Limited | Real estate | 2017 |
| Marlborough RD Apartments Ltd | Real estate | 2026 |
| Marley Collect's Ltd | Wholesale & retail | 2023 |
| Marley Cooling Tower Company (U.K.) Limited | Manufacturing | 1927 |
| Marliet Consulting Limited | Professional & scientific | 2024 |
| Marlin Plastics Limited | Manufacturing | 1998 |
| Marlland Ltd | Professional & scientific | 2024 |
| Marlow and Brown Limited | Real estate | 2016 |
| Marmalade Self-Publishing Limited | Information & communication | 2022 |
| Marmalade SKI School Limited | Administrative & support | 2010 |
| Marmaris Grill Nottingham Ltd | Hospitality | 2025 |
| Marmaris Restaurant (Nottingham) Ltd | Hospitality | 2025 |
| Marmaris Restaurant Ltd | Hospitality | 2025 |
| Marmaris Turkish Restaurant Notts Ltd | Hospitality | 2024 |
| Marnion Limited | Professional & scientific | 2001 |
| Maro Home Studio Ltd | Wholesale & retail | 2025 |
| Marper Limited | Real estate | 2014 |
| Marqell Partners Ltd | Wholesale & retail | 2025 |
| Marqen Ltd | Wholesale & retail | 2026 |
| Marrable Services Ltd | Professional & scientific | 2010 |
| Marrakesh Express Ltd | Hospitality | 2020 |
| Marraway Farm Developments Limited | Construction | 2021 |
| Marrio Fast Food Ltd | Hospitality | 2023 |
| Marriots Holdings Limited | Financial services | 2026 |
| Marriott Joinery Services Ltd | Construction | 2019 |
| Marriott Wholesale Limited | Wholesale & retail | 2024 |
| Marriotts Estate Agents Ltd | Real estate | 2020 |
| Marrline Ltd | Real estate | 2023 |
| Mars IT Solutions Limited | Information & communication | 2023 |
| Mars Music Ltd | Wholesale & retail | 2025 |
| Mars Retail Ltd | Wholesale & retail | 2020 |
| Marsh Bellofram Europe Limited | Wholesale & retail | 1906 |
| Marsh Holland Limited | Real estate | 2024 |
| Marsh Management Limited | Hospitality | 2013 |
| Marsh:Grochowski LLP | | 2003 |
| Marshall and Galley Plumbing & Heating Ltd | Construction | 2018 |
| Marshall ATA Ltd | Professional & scientific | 2018 |
| Marshall Geotechnical Consulting Ltd | Professional & scientific | 2025 |
| Marshall Holding Corporation Ltd | Financial services | 2026 |
| Marshall Industrial Supplies Limited | Wholesale & retail | 1999 |
| Marshall Properties & Renovations Ltd | Real estate | 2025 |
| Marshall Smalley Accountants Limited | Professional & scientific | 2002 |
| Marsham Court Limited | Real estate | 2018 |
| Marshman Business Consultancy Ltd | Administrative & support | 2019 |
| Marsi Housing CIC | Hospitality | 2025 |
| Marskil Services Limited | Professional & scientific | 2007 |
| Marss Solutions Limited | Information & communication | 2020 |
| Marston Homes Limited | Construction | 2004 |
| Marta Gomez Limited | Health & social care | 2013 |
| Martec Investments Limited | Professional & scientific | 2011 |
| Martem Collection Limited | Wholesale & retail | 2019 |
| Marthill International Limited | Wholesale & retail | 1997 |
| Martin Allen Flooring Limited | Other services | 2026 |
| Martin and Parker (Derby) Limited | Manufacturing | 1995 |
| Martin Baker Auditing Services Ltd | Professional & scientific | 2021 |
| Martin Davies Associates (Town and Country Planners) Limited | Professional & scientific | 2020 |
| Martin Dewis & Daughter Decorators Limited | Construction | 2016 |
| Martin Falcon Vehicle Logistics Limited | Transport & logistics | 2025 |
| Martin James Fireplaces Limited | Wholesale & retail | 2015 |