| Marsden & Searston Ltd | Construction | 2018 |
| Marshall's Events Ltd | Administrative & support | 2016 |
| Martin Cheung Limited | Information & communication | 2024 |
| Martin Cheung Photography Ltd | Professional & scientific | 2021 |
| Martin Uk.D Limited | Transport & logistics | 2005 |
| MAS Holding Investments Ltd | Real estate | 2025 |
| Masaac Limited | Real estate | 2026 |
| Masac Limited | Real estate | 2026 |
| Masquerade Music Publishing Ltd | Wholesale & retail | 2022 |
| Maths TUTORING2SUCCESS Limited | Education | 2013 |
| Matt Richardson Ltd | Wholesale & retail | 2018 |
| Matt Richardson Properties Ltd | Real estate | 2024 |
| Matt Selby Photography Ltd | Professional & scientific | 2019 |
| Matts Electrical Ltd | Construction | 2025 |
| Maverick & Bros Ltd | Hospitality | 2023 |
| Maverick HR Ltd | Administrative & support | 2005 |
| MAVI51 Ltd | Hospitality | 2025 |
| MAX Space Solutions Ltd | Other services | 2019 |
| Mayfield Furniture Limited | Wholesale & retail | 2002 |
| Mayfield Storage & Distribution Ltd | Transport & logistics | 2022 |
| Mbarodi Solutions Limited | Construction | 2016 |
| MCD Property Services Ltd | Construction | 2017 |
| Mcgee Technical Services Limited | Other services | 2001 |
| Mclaren Fire & Security Limited | Professional & scientific | 2025 |
| MD Living Ltd | Real estate | 2025 |
| MDS Roofing and Property Maintenance Ltd | Construction | 2025 |
| Medicore Health Ltd | Education | 2025 |
| Mekan Global Ltd | Professional & scientific | 2015 |
| Memorable Brands International Ltd | Wholesale & retail | 2026 |
| Memorials for YOU Ltd | Construction | 2013 |
| Merlinroute Limited | Arts & recreation | 1995 |
| Merritt Engineering Limited | Extraterritorial | 1996 |
| Merritt Plastics Limited | Extraterritorial | 1995 |
| Mersey Fair Air Limited | Transport & logistics | 2017 |
| Metmachex Swingarms Ltd | Wholesale & retail | 2017 |
| Metro Avenue 1960 Limited | Extraterritorial | 2014 |
| MF Therapeutic Care Ltd | Health & social care | 2024 |
| Mfak Management Limited | Information & communication | 2019 |
| MG Stock Auditing Ltd | Hospitality | 2026 |
| Mgjh Investments Limited | Financial services | 2025 |
| MHR Associates Ltd | Information & communication | 2011 |
| MHR Loom Bar Ltd | Hospitality | 2025 |
| Michael Skinner Limited | Construction | 2008 |
| Michal Kaczmarek Ltd | Transport & logistics | 2014 |
| Michal Mitura Ltd | Transport & logistics | 2019 |
| Microspan I.T Limited | Information & communication | 2011 |
| Mid-Derbyshire Motor Club Limited | Arts & recreation | 1983 |
| Midas Investments (Jvem) Limited | Financial services | 2024 |
| Midland CAD Design Limited | Information & communication | 2007 |
| Midland Surveying & Engineering Limited | Professional & scientific | 2002 |
| Midland Toyco Limited | Arts & recreation | 2012 |
| Midlands Garage Equipment Ltd | Manufacturing | 2012 |
| Midlands Maintenance Contractors Ltd | Construction | 2025 |
| Midlands Roof Repairs Ltd | Construction | 2020 |
| Migos Food Ltd | Hospitality | 2026 |
| Mihail Trandafir Ltd | Transport & logistics | 2017 |
| Miles Bramwell Digital Limited | Health & social care | 2019 |
| Miles Furniture Ltd | Wholesale & retail | 2011 |
| Miles-Bramwell Executive Services Limited | Professional & scientific | 1976 |
| Milledge Ltd | Construction | 2024 |
| Milton Mortgages Ltd | Financial services | 2026 |
| MIM Ltd | Manufacturing | 2024 |
| Mimi's Soul Food and Lounge Bar Ltd | Hospitality | 2014 |
| Mind Over Matter Level UP Ltd | Other services | 2025 |
| Mind Over Matter Nutrition and Fitness Ltd | Health & social care | 2021 |
| Mitchell Sports Limited | Wholesale & retail | 2013 |
| Mlimb Arbitrage Ltd | Wholesale & retail | 2025 |
| MM Media Solutions Ltd | Information & communication | 2024 |
| MM Scaffolding Solutions Ltd | Construction | 2023 |
| MM Supported Employment Ltd | Administrative & support | 2023 |
| MMB Lifting Services Ltd | Construction | 2014 |
| MMD Mining Machinery Developments Ltd | Manufacturing | 1978 |
| MMD Summerfield Holdings Ltd | Professional & scientific | 2004 |
| MMD Summerfield Ltd | Manufacturing | 1984 |
| MNK Associates Limited | Professional & scientific | 2016 |
| Mnkj Property Limited | Real estate | 2025 |
| Mobile Telecoms Transport Ltd | Construction | 2019 |
| Mobility in Motion International Ltd | Manufacturing | 2022 |
| Mobility in Motion Ltd | Manufacturing | 2022 |
| Modeuro Consulting Ltd | Professional & scientific | 2019 |
| Modular Management Corporation Ltd | Professional & scientific | 2020 |
| Modular Telecom Limited | Information & communication | 2020 |
| Mondayfoodreview Ltd | Information & communication | 2025 |
| Monk on Ltd | Wholesale & retail | 2021 |
| Monkey Wrench Productions Limited | Information & communication | 2010 |
| Monkeymole Media Limited | Information & communication | 2025 |
| Monsieur Clothing Limited | Wholesale & retail | 2025 |
| Montel Properties Management Limited | Hospitality | 2023 |
| Monty’S Motorhomes Ltd | Wholesale & retail | 2021 |
| Moonhouse Music Ltd | Wholesale & retail | 2022 |
| Moorland Aerial Sites Limited | Construction | 2019 |
| Morley Trading Ltd | Water & waste | 2017 |
| Motorcycle Tyre Specialists Limited | Wholesale & retail | 2004 |
| Motoring Admin Services Ltd | Other services | 2025 |
| Mountain Newco Co Ltd | Professional & scientific | 2023 |
| Mountain PUB Company Limited | Hospitality | 2022 |
| Mountain PUB Services Ltd | Other services | 2023 |
| MRH Road Hire Limited | Construction | 2019 |
| MSM Lettings Ltd | Real estate | 2022 |
| Mstm Solutions Ltd | Other services | 2021 |