| Mattimore Wealth and Wellbeing Ltd | Professional & scientific | 2023 |
| MAX Mechanicx Ltd | Wholesale & retail | 2021 |
| Maxi-Low (UK) Limited | Manufacturing | 2012 |
| Mayfield House Residential Care Home Limited | Administrative & support | 1997 |
| Mayflower Management Solutions Limited | Professional & scientific | 2021 |
| Mayhua Limited | Hospitality | 2025 |
| Mayzo Limited | Transport & logistics | 2026 |
| MBS IT Ltd | Information & communication | 2012 |
| MC Trading (Cheshire) Limited | Wholesale & retail | 2010 |
| MCC Surfacing Limited | Construction | 2024 |
| Mcevoy Financial Consultants Limited | Construction | 2019 |
| MCJ Developments Ltd | Administrative & support | 2018 |
| MCK Cleaning Ltd | Administrative & support | 2019 |
| Mckenzie Mckenzie Ltd | Professional & scientific | 2022 |
| MCQ Healthcare Consultancy Ltd | Health & social care | 2020 |
| MCT Civils Limited | Construction | 2025 |
| MD Project Safety Ltd | Professional & scientific | 2005 |
| MD Properties (Crewe) Ltd | Real estate | 2021 |
| MDB Digital Limited | Information & communication | 2023 |
| Mdentrepreneur Ltd | Wholesale & retail | 2025 |
| MDL Holdings Cheshire Limited | Financial services | 2011 |
| MDR Haulage Ltd | Transport & logistics | 2023 |
| ME Lifestyle Limited | Administrative & support | 2019 |
| Meadow One Ltd | Agriculture & fishing | 2024 |
| MEC Building Management Solutions Limited | Extraterritorial | 2009 |
| Medex Protect Limited | Administrative & support | 2013 |
| Medica Packaging Limited | Manufacturing | 1993 |
| Medicare Solutions (M) Ltd | Health & social care | 2024 |
| Medication Packaging Holdco Limited | Financial services | 2019 |
| Medieng Consulting Limited | Other services | 2012 |
| Medieval Events Limited | Hospitality | 2021 |
| Medina Fast Food Limited | Hospitality | 2021 |
| Medtrade Products Limited | Manufacturing | 1999 |
| Meem Cheshire Ltd | Hospitality | 2024 |
| Meera Medical Ltd | Health & social care | 2018 |
| Meibe Limited | Hospitality | 2024 |
| Meison Ltd | Information & communication | 2025 |
| Mel's Kitchen Crewe Ltd | Hospitality | 2025 |
| Mellor & Son’S Ltd | Administrative & support | 2023 |
| Melvicmakeup Academy Limited | Arts & recreation | 2015 |
| Memory Box Flowers Limited | Other services | 2022 |
| Mendieta Ltd | Information & communication | 2014 |
| Mental Health 360 Community Interest Company | Health & social care | 2026 |
| Meop Limited | Construction | 2017 |
| Mercia Finance Limited | Financial services | 2023 |
| Mercury Roof Conversions Ltd | Construction | 2021 |
| Merseyside Turnaround and Development Company Limited | Professional & scientific | 2005 |
| Metals Online Limited | Wholesale & retail | 2022 |
| Mettyop Ltd | Manufacturing | 2018 |
| Mews Consultants Ltd | Information & communication | 2023 |
| Mezzaluna Gifts Limited | Wholesale & retail | 2013 |
| Mf.Building.Gardering Limited | Construction | 2023 |
| MG Clinical Ltd | Professional & scientific | 2016 |
| MGM Automotive 24/7 Ltd | Wholesale & retail | 2022 |
| Mgmmn Solutions Ltd | Information & communication | 2018 |
| MGP Capital Limited | Administrative & support | 2019 |
| MGT Advisory Services Ltd | Professional & scientific | 2021 |
| MHB Investment Group Limited | Health & social care | 2025 |
| MIA Boutique (Nantwich) Ltd | Wholesale & retail | 2022 |
| Mibec Limited | Wholesale & retail | 2010 |
| Michael Perry Consultancy Limited | Professional & scientific | 2009 |
| Michael.P.Haigh Limited | Construction | 2004 |
| Micklewright Garage Ltd | Wholesale & retail | 2026 |
| Microgrower Limited | Administrative & support | 2001 |
| MID Cheshire Table Tennis Club CIC | Arts & recreation | 2026 |
| Middleton Web Design Limited | Information & communication | 2020 |
| Middletons Travel Limited | Administrative & support | 2024 |
| Middlewich Street Dental Practice Ltd | Health & social care | 2011 |
| Midland Furniture Auctions Limited | Wholesale & retail | 2005 |
| Midnight Mountain Ltd | Information & communication | 2022 |
| Mighty Oats Limited | Extraterritorial | 1965 |
| Mihai Giza Ltd | Health & social care | 2022 |
| Mihälsa Limited | Information & communication | 2024 |
| Miilana Ltd | Hospitality | 2023 |
| Mike Webster & SON Ltd | Administrative & support | 2011 |
| Mikes Constructions Group Ltd | Construction | 2019 |
| Mikro Coaches Limited | Transport & logistics | 2013 |
| Mila LDN Limited | Hospitality | 2026 |
| Mila London Limited | Hospitality | 2026 |
| Milalux Ltd | Wholesale & retail | 2023 |
| Mile Deep Ltd | Wholesale & retail | 2019 |
| Milestone Ecommerce Limited | Information & communication | 2008 |
| Milestone Group (Holdings) Ltd | Professional & scientific | 2014 |
| Milestone Insurance Consultants Limited | Financial services | 2002 |
| Milexi Ltd | Professional & scientific | 2021 |
| Mill Cross Management Company Limited | Real estate | 1998 |
| Mime Solutions Limited | Professional & scientific | 2003 |
| Mimigo Ltd | Wholesale & retail | 2024 |
| Minerva Defence & Security Limited | Administrative & support | 2023 |
| Mini and ME Play Limited | Hospitality | 2025 |
| Minifords Limited | Wholesale & retail | 2026 |
| Ministry of Yoga and Wellbeing Ltd | Arts & recreation | 2015 |
| Minshull Hall Barns Management Company Limited | Other services | 2005 |
| Mint Chem Ltd | Wholesale & retail | 2023 |
| Mirage Legion Limited | Transport & logistics | 2019 |
| Miro 83 Ltd | Transport & logistics | 2019 |
| Miro OUD Limited | Wholesale & retail | 2026 |
| Miro Vehicle Recovery Ltd | Wholesale & retail | 2021 |
| Mischief Made Ltd | Wholesale & retail | 2024 |
| Misha's UK Jewellery Ltd | Manufacturing | 2023 |