| Mobile Plus Cannock Limited | Wholesale & retail | 2025 |
| Mobile Vehicle Diagnostics Limited | Wholesale & retail | 2025 |
| Mobile Zone Retail Limited | Information & communication | 2015 |
| Mobilechippy Ltd | Construction | 2018 |
| Mobility & Lifestyle Bedworth Ltd | Wholesale & retail | 2011 |
| Mobility & Lifestyle Grantham Ltd | Wholesale & retail | 2011 |
| Mobility & Lifestyle Hinckley Ltd | Wholesale & retail | 2011 |
| Mobility & Lifestyle Holdings Ltd | Professional & scientific | 2013 |
| Mobility & Lifestyle Limited | Wholesale & retail | 2006 |
| Mobility & Lifestyle Tamworth Limited | Wholesale & retail | 2009 |
| Mobility and Lifestyle Melton Ltd | Wholesale & retail | 2012 |
| Mobility and Lifestyle Support Ltd | Manufacturing | 2015 |
| Mobiquip Limited | Wholesale & retail | 2017 |
| Mobiton E-Commerce Ltd | Wholesale & retail | 2023 |
| Mochimocha Limited | Information & communication | 2015 |
| Mode Renovations Limited | Real estate | 2023 |
| Mode Resin Ltd | Administrative & support | 2026 |
| Modeled Ltd | Manufacturing | 2018 |
| Modern & Classic Vehicle Security Ltd | Wholesale & retail | 2026 |
| Modern & Classic Vehicle Services Ltd | Wholesale & retail | 2021 |
| Modern & Heritage Limited | Wholesale & retail | 2024 |
| Modern China Limited | Hospitality | 2024 |
| Modern Construction and Maintenance Company Limited | Manufacturing | 2025 |
| Modern Logistics Limited | Transport & logistics | 2018 |
| Modernized Trade Solutions Ltd | Manufacturing | 2026 |
| Modrophenia Clothing Ltd | Wholesale & retail | 2017 |
| Modrophenia Ltd | Wholesale & retail | 2021 |
| Modular Solutions Online Limited | Manufacturing | 2022 |
| Moffatt BS Limited | Professional & scientific | 2013 |
| Mohammad Nawid Omari Ltd | Wholesale & retail | 2025 |
| Mohammad Youns Ltd | Wholesale & retail | 2025 |
| Mohammed Ajmal Uddin Ltd | Construction | 2024 |
| Mohar Digital Ltd | Wholesale & retail | 2024 |
| Moharest Ltd | Administrative & support | 2024 |
| Mohyeldin Ltd | Extraterritorial | 2021 |
| MOI Venn Limited | Other services | 2025 |
| Moinswan Ltd | Administrative & support | 2024 |
| Mojaa’S Automotive Ltd | Wholesale & retail | 2025 |
| Moldwel Products Limited | Manufacturing | 2003 |
| Moldwel Properties Limited | Real estate | 2003 |
| Moma London Ltd | Other services | 2021 |
| Moments Beauty Centre Ltd | Other services | 2012 |
| MOMHUSTLE01 Limited | Wholesale & retail | 2025 |
| Mona Transport and Export Ltd | Transport & logistics | 2025 |
| Money Empowerment Ltd | Information & communication | 2019 |
| Money Marketer Limited | Professional & scientific | 2016 |
| Monkeyzoo Ltd | Manufacturing | 2022 |
| Monkhall Fishery's LLP | | 2013 |
| Monsoon Enterprises Limited | Real estate | 2002 |
| Montague Canin Limited | Professional & scientific | 1950 |
| Montvane Serviced Stays Ltd | Real estate | 2025 |
| Monty's Property & Co Ltd | Real estate | 2026 |
| Monza Motor House Limited | Wholesale & retail | 2016 |
| Monzaline Limited | Real estate | 1989 |
| Monzee Limited | Hospitality | 2025 |
| Moon Light Ices Ltd | Hospitality | 2025 |
| Moon Services UK Limited | Other services | 2020 |
| Moonl Limited | Hospitality | 2025 |
| Moonpath Limited | Construction | 2017 |
| Moonraker Books Limited | Wholesale & retail | 1998 |
| Moore Cafe Limited | Hospitality | 2007 |
| Moore Marine Limited | Arts & recreation | 2005 |
| Moorhouse Property Agent Limited | Real estate | 2023 |
| Moot Point Media Ltd | Professional & scientific | 2021 |
| Mooving Guys Ltd | Wholesale & retail | 2023 |
| Moowal Ltd | Transport & logistics | 2026 |
| Morad African Groceries Store Limited | Wholesale & retail | 2026 |
| Moran Construction and Development (2025) Ltd | Construction | 2025 |
| Mordiciux Ltd | Administrative & support | 2024 |
| More Than Carpets Limited | Administrative & support | 2021 |
| Moreblessings Limited | Administrative & support | 2020 |
| Moredarest Ltd | Transport & logistics | 2024 |
| Morgan Investment Holdings Limited | Financial services | 2026 |
| Morgan Leisure Holdings Ltd | Hospitality | 2008 |
| Morgan Management Services LLP | | 2024 |
| Morgan's Transport Limited | Transport & logistics | 2025 |
| Morgatron Logistics Limited | Transport & logistics | 2013 |
| Morgzz Ltd | Arts & recreation | 2021 |
| Moriangan Ltd | Transport & logistics | 2024 |
| Morningstar MFG Limited | Manufacturing | 2017 |
| Morris & Farmer Property Co Ltd | Real estate | 2025 |
| Morris & Warren (Alrewas) Limited | Construction | 2023 |
| Morris & Warren (Edial) Limited | Construction | 2020 |
| Morris Cooper (Holdings) Limited | Professional & scientific | 2016 |
| Morris Exterior Cleaning Ltd | Administrative & support | 2025 |
| Morrison Mcconnell Limited | Wholesale & retail | 2020 |
| Mortgage Assured Ltd | Financial services | 2005 |
| Mortgage Chat Ltd | Information & communication | 2025 |
| Mortgage Hypermarket Limited | Financial services | 2002 |
| Mortgagenie Ltd | Financial services | 2020 |
| Morthan Construction Limited | Construction | 2025 |
| Morthan Property Ltd | Real estate | 2016 |
| Mortimer's Maintenance Limited | Construction | 2015 |
| Mortivzan Ltd | Transport & logistics | 2024 |
| Morton and Crowder Limited | Manufacturing | 1896 |
| Morvan Consultant Services Ltd | Administrative & support | 2016 |
| Mosaic : Neuro - Inclusive Support C.I.C. | Education | 2025 |
| Mosala Corner Limited | Hospitality | 2025 |
| Moshadest Ltd | Transport & logistics | 2024 |
| Mossley Community Connections CIC | Health & social care | 2023 |