| Merynton Close Management Company Limited | Households | 2020 |
| Metaclass Software Ltd | Information & communication | 2014 |
| Metamorphic Furniture Ltd | Manufacturing | 2015 |
| Metrics Property Consultants Limited | Professional & scientific | 2017 |
| Metropolitan Apartments RTM Company Limited | Households | 2011 |
| Meyer Orthopaedics Limited | Health & social care | 2018 |
| MF Supplements Ltd | Wholesale & retail | 2025 |
| MFB Housing Limited | Real estate | 2022 |
| Mfic | Financial services | 2017 |
| MG Dental Ltd | Real estate | 2023 |
| MG Services WM Ltd | Health & social care | 2023 |
| MGG Retail Group Ltd | Wholesale & retail | 2025 |
| Mgkb Holdings Limited | Financial services | 2026 |
| MGM Locums Ltd | Professional & scientific | 2010 |
| MH Hoof Care Ltd | Agriculture & fishing | 2020 |
| MH Plumbing Ltd | Construction | 2018 |
| MHF Contract Furniture Limited | Manufacturing | 2003 |
| MHL Strategic Land Limited | Financial services | 2018 |
| MI Accountancy Limited | Professional & scientific | 2023 |
| MI Battery Systems Limited | Manufacturing | 2021 |
| MI Renewable Energy Limited | Energy | 2020 |
| Micarlib Ltd | Professional & scientific | 2019 |
| Michael Cruise Architects Ltd | Professional & scientific | 2019 |
| Mick Hills Landscaping Limited | Administrative & support | 2017 |
| Micklewood Dairy Farm Ltd | Agriculture & fishing | 2025 |
| Micro Data Technologies Ltd | Administrative & support | 2024 |
| Microvideo-Shrewsbury Limited | Information & communication | 2012 |
| MID Shropshire Vintage Club Limited | Arts & recreation | 1990 |
| MID Wales HR Ltd | Administrative & support | 2021 |
| Midas Property Developments Ltd | Real estate | 2024 |
| Middlebrook View Management Limited | Households | 2010 |
| Middleton Chambers Management Company Limited | Real estate | 2022 |
| Midland Cottages Limited | Real estate | 2026 |
| Midland Landscaping Limited | Administrative & support | 1964 |
| Midland Life and Mortgage Corporation Limited | Financial services | 1993 |
| Midlands GUN Services Ltd | Manufacturing | 2015 |
| Midlands Surgical Education Limited | Health & social care | 2024 |
| Midlands Woodchip Ltd | Manufacturing | 2014 |
| Midshire Labs Ltd | Wholesale & retail | 2025 |
| MIG Ceilings and Partitions Ltd | Construction | 2018 |
| Mighty Oak Marketing Ltd | Professional & scientific | 2019 |
| Mike and Nicola Dalton Limited | Wholesale & retail | 2012 |
| Mike Burrows Electrical Contractor Limited | Construction | 2003 |
| Mike Perkins Art Limited | Arts & recreation | 2022 |
| Mike Roberts Electrical Limited | Construction | 2022 |
| Mike Roberts Electrical Services Ltd | Construction | 2006 |
| Mike Roberts Holdings Ltd | Real estate | 2018 |
| Milford Estates Ltd | Construction | 2023 |
| Milford FOX Limited | Construction | 2014 |
| Milford Investments Limited | Construction | 1997 |
| Military Precision Measurements Ltd | Professional & scientific | 2020 |
| Milkyy Limited | Professional & scientific | 2025 |
| Mill Court (Barnsley) Management Limited | Households | 2007 |
| Mill Court Freehold Apartments (Shrewsbury) Limited | Extraterritorial | 2012 |
| Mill Court Shrewsbury Management Company Limited | Extraterritorial | 2010 |
| Mill Drive Management Company Limited | Households | 2013 |
| Mill House Stud (Shropshire) Limited | Administrative & support | 2007 |
| Millard & Lancaster Limited | Wholesale & retail | 2011 |
| Millenium Systems Limited | Information & communication | 1988 |
| Miller Enterprises (MES) Limited | Real estate | 1999 |
| Millers Gate Management Company Limited | Households | 2022 |
| Millers of Netley Limited | Hospitality | 2008 |
| Millpool Close Residents Company Limited | Households | 1991 |
| Millside Quay (Bristol) Management Limited | Real estate | 1992 |
| Millstar Limited | Professional & scientific | 1990 |
| Milward Bait & Tackle Ltd | Wholesale & retail | 2025 |
| Milward Scaffold Services Limited | Construction | 2014 |
| Mim’S Studio Limited | Other services | 2013 |
| Mind OUT for Music | Other services | 2009 |
| Mine Water Management Ltd | Professional & scientific | 2023 |
| Mineral Advice Limited | Agriculture & fishing | 2025 |
| Minerva SRM Ltd | Professional & scientific | 2014 |
| MINHAL123 Limited | Health & social care | 2021 |
| Minshull Court Management Company Limited | Households | 2020 |
| Minsterley Motors Ltd | Transport & logistics | 2021 |
| Mint Media Capital Limited | Professional & scientific | 2014 |
| Mipower Limited | Wholesale & retail | 2020 |
| Mipower Technology Limited | Financial services | 2012 |
| Mirralis Ltd | Construction | 2025 |
| Mirror Mirror Group Limited | Other services | 2017 |
| Mirror Mirror Retail Limited | Wholesale & retail | 2025 |
| Misdp Solutions Ltd | Professional & scientific | 2022 |
| Mitchells Brook Management Limited | Households | 2006 |
| Mitra Marketing Ltd | Professional & scientific | 2005 |
| Miwai Ltd | Information & communication | 2023 |
| Mixed Emulsions Painting & Decorating Ltd | Construction | 2011 |
| MJ & EM Services Limited | Professional & scientific | 2008 |
| MJ Refrigeration Transport (North) Ltd | Transport & logistics | 2021 |
| Mj&Co Accountants Limited | Professional & scientific | 2012 |
| Mjandrew Ltd | Information & communication | 2022 |
| Mjda Property Ltd | Real estate | 2022 |
| MJH Construction (Shrewsbury) Ltd | Construction | 2019 |
| MJH Contract Services Ltd | Construction | 1996 |
| MJH Groundwork (Shrewsbury) Ltd | Construction | 2017 |
| MJH Plant Ltd | Administrative & support | 2019 |
| Mjpa Hire Limited | Construction | 1999 |
| MKS Plant Training and Testing Ltd. | Professional & scientific | 2008 |
| ML Developments (Shrewsbury) Limited | Construction | 2018 |
| ML Developments (Shropshire) Limited | Construction | 2018 |
| MLM Financial Ltd. | Financial services | 2004 |