| Met-Fab Scotland Limited | Manufacturing | 2011 |
| Methven Indian Limited | Hospitality | 2026 |
| MF Roofing Ltd | Construction | 2023 |
| MFM Security Systems Ltd | Public administration | 2026 |
| MG Joinery & Developments Ltd. | Construction | 2013 |
| MG Vending Solutions Ltd | Wholesale & retail | 2025 |
| MGB Fence and Land Ltd | Agriculture & fishing | 2025 |
| MGM Fire & Electrical Services Ltd | Professional & scientific | 2010 |
| Micah Photography Ltd | Professional & scientific | 2025 |
| Micboo Ltd | Information & communication | 2019 |
| Michael S. Sands Limited | Agriculture & fishing | 2002 |
| Michael Sands Builders Ltd | Construction | 2017 |
| Miconex Ltd. | Professional & scientific | 2012 |
| Micro:Mag CIC | Manufacturing | 2019 |
| Midlothian Ventilation Services Ltd | Manufacturing | 2019 |
| Mike & Lena Singer Ltd | Hospitality | 2011 |
| Miles Together LLP | | 2025 |
| Millcrest Properties Limited | Construction | 1986 |
| Millden Agricultural LLP | | 2004 |
| Millden Sporting LLP | | 2004 |
| Millearne Weddings Ltd | Administrative & support | 2019 |
| Miller & Steel Limited | Information & communication | 2022 |
| Miller - Watt Ltd | Construction | 2023 |
| Millpark 1965 Limited | Real estate | 2018 |
| Millrodgie Limited | Agriculture & fishing | 2022 |
| Mills Contractors Limited | Transport & logistics | 2004 |
| Milton Burn Developments Limited | Real estate | 2007 |
| Mimi Productions Ltd | Real estate | 2024 |
| Minds and Manes Limited | Other services | 2026 |
| Mindspace Limited | Other services | 1997 |
| Minhas Comercial Limited | Administrative & support | 2020 |
| Minrec Limited | Mining & quarrying | 2005 |
| MIR5 Ltd | Wholesale & retail | 2017 |
| Mirawdale Ltd | Hospitality | 2026 |
| Miss Forsyth Limited | Wholesale & retail | 2003 |
| MJA Property Estates Ltd | Real estate | 2022 |
| MJA Sports Ltd | Wholesale & retail | 2017 |
| MJM Properties (Perth) Limited | Real estate | 2021 |
| MK Blacksmith Ltd | Manufacturing | 2018 |
| MK Tiler Ltd | Construction | 2016 |
| ML Holdings Scotland Ltd | Construction | 2017 |
| MM Energy (UK) Ltd | Professional & scientific | 2007 |
| Mmcf Properties Ltd | Real estate | 2020 |
| Mmec Geoenvironmental Ltd | Professional & scientific | 2010 |
| Moark Limited | Real estate | 2009 |
| Mobile Healthcare Networks Limited | Professional & scientific | 2006 |
| Mobvue Ltd | Information & communication | 2021 |
| Moes Chefs Ltd | Hospitality | 2012 |
| Moldova Perth Limited | Wholesale & retail | 2022 |
| Mollyletts Limited | Real estate | 2018 |
| Momentum Warranties Limited | Wholesale & retail | 2005 |
| Moncur Roofing Limited | Extraterritorial | 2010 |
| Mondo Foods Limited | Hospitality | 2025 |
| Mondoburger Ltd | Hospitality | 2022 |
| Monmor Living Limited | Wholesale & retail | 2025 |
| Monteith Steen LLP | | 2010 |
| Monzie Hotel Land Ltd | Construction | 2025 |
| MOR Inc. Limited | Financial services | 2023 |
| MOR Management Limited | Professional & scientific | 2026 |
| MOR Residential Limited | Households | 2023 |
| Moral Tribe Games Ltd | Health & social care | 2020 |
| Moray Speyside Ltd | Administrative & support | 2016 |
| Mordor Gundogs Ltd | Agriculture & fishing | 2023 |
| Mordor Hunting Ltd | Arts & recreation | 2026 |
| Mordor Media Ltd | Other services | 2026 |
| Mordor Property Ltd | Real estate | 2019 |
| Morgan Homes (Scotland) Limited | Construction | 2004 |
| Morris Leslie Auctions Limited | Wholesale & retail | 2010 |
| Morris Leslie Holdings Limited | Professional & scientific | 2023 |
| Morris Leslie Limited | Real estate | 1985 |
| Morris Leslie Plant Hire Ltd | Administrative & support | 2000 |
| Morris Leslie Plant Limited | Administrative & support | 2008 |
| Morris Leslie Property Limited | Real estate | 2013 |
| Morris Leslie Villages Limited | Hospitality | 2021 |
| Morris Lets Limited | Households | 2023 |
| Morris Young (Perth) Limited | Transport & logistics | 1963 |
| Morrison Scotch Whisky Distillers Limited | Manufacturing | 1982 |
| Motodrive Auto Works Ltd | Manufacturing | 2025 |
| Motorhome Buyers Scotland Ltd | Wholesale & retail | 2026 |
| Motorhome Services (Scotland) Limited | Wholesale & retail | 2011 |
| Motorparts Supply Limited | Wholesale & retail | 2014 |
| Motortrade Support Ltd. | Wholesale & retail | 2018 |
| Motorvate Therapies Limited | Health & social care | 2013 |
| Move-Able Limited | Manufacturing | 2016 |
| MP Joinery Perth Ltd | Construction | 2021 |
| Mpcontractor Scotland Ltd | Agriculture & fishing | 2025 |
| MR Mechanic Solutions Ltd | Wholesale & retail | 2025 |
| MR Scrubs Ltd | Administrative & support | 2025 |
| MRL Sales Ltd | Wholesale & retail | 2022 |
| MS Landscaping & Groundworks Ltd | Administrative & support | 2025 |
| MSR Plumbing & Heating Ltd | Administrative & support | 2012 |
| MST Aviation Limited | Transport & logistics | 2002 |
| MTM Car Sales Ltd | Wholesale & retail | 2024 |
| Muckmedden Ltd | Arts & recreation | 2013 |
| Muhammad Burhan Rashid Limited | Hospitality | 2025 |
| Muirhall Associates Limited | Professional & scientific | 2017 |
| Muirhouses Limited | Construction | 2022 |
| Muirton P.O. Ltd | Transport & logistics | 2024 |
| Mullardoch Hydro Ltd | Energy | 2014 |
| MULTI-SERVICES.P.N.1 Ltd | Construction | 2024 |