| Montague Simon Investments Limited | Professional & scientific | 1989 |
| Moore Jones Property Consultancy Limited | Real estate | 2019 |
| Moorland CFO Solutions Limited | Professional & scientific | 2023 |
| Morgan Clarke Properties Ltd | Real estate | 2020 |
| Morgan Signs and Design Limited | Manufacturing | 2009 |
| Morgans Trading Limited | Construction | 2025 |
| Morro GB Limited | Construction | 2025 |
| Morro Group Limited | Professional & scientific | 2016 |
| Morro Innovation Hub Limited | Manufacturing | 2025 |
| Morro Land Limited | Construction | 2007 |
| Morro Partnerships Limited | Construction | 1988 |
| Morweb Carpentry Ltd | Construction | 2025 |
| Moss Cottage Management Limited | Households | 2023 |
| Moss Services Limited | Construction | 2025 |
| Mossfix Limited | Professional & scientific | 2026 |
| Moto-Race Paint Ltd | Wholesale & retail | 2019 |
| Motorcycle Essentials Limited | Other services | 2002 |
| Moult Investments Limited | Real estate | 2019 |
| Mount View Management Company 2024 Ltd | Households | 2024 |
| MPG Adblue Solutions Ltd | Manufacturing | 2024 |
| MPG Tuning Limited | Manufacturing | 2012 |
| MPH (Midlands) Limited | Other services | 2005 |
| MPM Electrical Services Limited | Energy | 2005 |
| MR DJ Ltd | Wholesale & retail | 2020 |
| MR Popple's Chocolate Limited | Manufacturing | 2019 |
| MRD Commercial Consultants Ltd | Professional & scientific | 2017 |
| MRH Construction and Builders Limited | Construction | 2016 |
| MRS R'S Language Academy Limited | Education | 2020 |
| Msarterberry Limited | Professional & scientific | 2024 |
| MSD Midlands Properties Ltd | Real estate | 2025 |
| MT Transporting Solutions Ltd | Transport & logistics | 2026 |
| MT Utilities Ltd | Energy | 2020 |
| MT Vehicle Solutions Limited | Wholesale & retail | 2023 |
| MTR Training (UK) Ltd | Education | 2007 |
| Mubu Travel Limited | Administrative & support | 2020 |
| Mues Ltd | Professional & scientific | 2018 |
| Mulberry Court Midlands Limited | Real estate | 2025 |
| Mulla Group Ltd | Households | 2023 |
| Multi-Temp (UK) Limited | Construction | 2007 |
| Multi-Temp Developments Limited | Real estate | 2024 |
| Multi-Temp Holdings Limited | Financial services | 2019 |
| Multi-Temp Renewables Limited | Financial services | 2021 |
| Multi-Temp Services Limited | Extraterritorial | 2009 |
| Multifloor (Walsall) Limited | Construction | 1993 |
| MUNASHE1 Limited | Health & social care | 2012 |
| Murray Control Systems Ltd | Construction | 2003 |
| Musxcel Limited | Education | 2023 |
| MW Electrical Testing Ltd | Construction | 2024 |
| Mwood Electrical Ltd | Construction | 2026 |
| MX (Handling Equipment) UK Limited | Administrative & support | 1971 |
| MXL Investments Limited | Professional & scientific | 2020 |
| My School Ambulance Limited | Education | 2020 |
| Mylovian Property Services Limited | Real estate | 2022 |
| Mypropertylets Ltd | Real estate | 2022 |
| Mysc Property Limited | Real estate | 2025 |
| Mythic Loot Ltd | Wholesale & retail | 2025 |
| Mythros Support Services Limited | Information & communication | 2025 |
| N B Auto Electrical Limited | Wholesale & retail | 2019 |
| N Cooper Groundwork Contractor Limited | Construction | 2002 |
| N Palmer Consulting Ltd | Professional & scientific | 2019 |
| N R W Holdings Limited | Extraterritorial | 2003 |
| N.D.F. Business Services Limited | Other services | 2012 |
| N.I.P. Cleaning Contracts Ltd. | Administrative & support | 1998 |
| N.J. Heminsley Limited | Construction | 2002 |
| N.T.B. Builders Limited | Construction | 2023 |
| Nacles Care Ltd | Health & social care | 2024 |
| Naldash Ltd | Professional & scientific | 2026 |
| Nanny Brown's Ltd | Hospitality | 2022 |
| Naseeb Holdings Ltd | Administrative & support | 2019 |
| Nash B H Ltd | Real estate | 2020 |
| Nash Properties Ltd | Administrative & support | 2019 |
| Nathan Bond Services Limited | Information & communication | 2018 |
| National Electrical Testing Engineers Ltd | Manufacturing | 2023 |
| National Fire Extinguisher Training Limited | Education | 2020 |
| National Floor Preparation Centres Limited | Administrative & support | 2001 |
| National Plant Solutions Limited | Manufacturing | 2017 |
| Nationwide Graphics Application Ltd | Wholesale & retail | 2026 |
| Nationwide Window Services Limited | Construction | 2017 |
| Natural Nails (Cannock) Limited | Other services | 2025 |
| Navenby Invest Ltd | Health & social care | 2023 |
| NBP Services Ltd | Professional & scientific | 2026 |
| NBS Rogers Properties Limited | Households | 2024 |
| NC Enterprises Ltd | Information & communication | 2017 |
| NDO Global Integrity Limited | Administrative & support | 2026 |
| Neat N Tidy Property Limited | Administrative & support | 2005 |
| Neckar Investments Ltd | Administrative & support | 1999 |
| Neil Hawkins Plant Sales Ltd | Wholesale & retail | 2025 |
| Neil Hawkins Plant Services Ltd | Manufacturing | 2013 |
| Neil Smith Automatic Transmission Specialists Ltd | Wholesale & retail | 2015 |
| Neptune Rentals Limited | Real estate | 2016 |
| Nesirky Carpentry Limited | Construction | 2016 |
| Nest Construction and Consultancy Ltd | Construction | 2025 |
| Netclix Ltd | Information & communication | 2020 |
| Netklix Limited | Information & communication | 1999 |
| New Design Kitchens (Cannock) Limited | Manufacturing | 2018 |
| New Design Kitchens Limited | Wholesale & retail | 1996 |
| New Haus Properties Limited | Real estate | 2022 |
| New Hayes Park Limited | Households | 2018 |
| New Homes Mortgage Services LLP | | 2014 |
| Newman Plumbing & Heating Limited | Construction | 2007 |