| Miramar Judo Academy Ltd | Arts & recreation | 2015 |
| Mirzopoly Ltd | Real estate | 2025 |
| MIS Buildings Limited | Extraterritorial | 2005 |
| MIS Group Limited | Extraterritorial | 2005 |
| Miserable Film Limited | Information & communication | 2016 |
| Miss Million Limited | Information & communication | 2025 |
| Mission in Hair Ltd | Other services | 2010 |
| Missperfectuk Limited | Wholesale & retail | 2017 |
| Mistlawn Limited | Households | 2002 |
| Misura Investments Ltd | Real estate | 2024 |
| Misura Limited | Administrative & support | 2011 |
| Mitchell Drywall Services Limited | Construction | 2019 |
| Mitegra Ltd | Information & communication | 2023 |
| Mitem Ltd | Transport & logistics | 2024 |
| Mith Global Ltd | Wholesale & retail | 2018 |
| Mixbabies Ltd | Wholesale & retail | 2024 |
| MJ Africa Stores Limited | Wholesale & retail | 2025 |
| MJ Landscapes & Services Ltd | Administrative & support | 2021 |
| MJ LEE Plastering Limited | Construction | 2020 |
| MJ Moving Solutions Ltd | Transport & logistics | 2025 |
| MJ Software Consulting Limited | Information & communication | 2020 |
| MJ Water Services Ltd | Construction | 2025 |
| MJ Yorkshire Ltd | Financial services | 2023 |
| MJ49 Holdings Limited | Financial services | 2019 |
| MJA Fabtech Ltd | Manufacturing | 2025 |
| MJA Welding Site Services Ltd | Construction | 2024 |
| Mjcommerce Limited | Wholesale & retail | 2019 |
| MJL Construction Ltd | Construction | 2026 |
| MJO Services Limited | Manufacturing | 2003 |
| MJR Hose Services Ltd | Manufacturing | 2022 |
| MJR Plant Hire Limited | Construction | 2001 |
| MJT Motors Limited | Wholesale & retail | 2023 |
| MK & MK Properties Ltd | Real estate | 2020 |
| MK & MK Properties Yorkshire Limited | Real estate | 2023 |
| MK Beauty & Aesthetics Limited | Other services | 2025 |
| MK Marketing System Ltd | Professional & scientific | 2015 |
| MK Medical Services Ltd | Health & social care | 2019 |
| MK Therapy Ltd | Health & social care | 2024 |
| MK Valeting&Detailing Ltd | Administrative & support | 2024 |
| MKI Property Developments Limited | Real estate | 2023 |
| MKK Housing Ltd | Real estate | 2025 |
| Mkoc Ltd | Other services | 2024 |
| Mkulu Ltd | Professional & scientific | 2025 |
| MKW Plumbing and Heating Limited | Construction | 2025 |
| ML Nkomo Limited | Health & social care | 2026 |
| ML9 Consulting Ltd | Administrative & support | 2018 |
| MLA Developments Ltd | Construction | 2018 |
| MLA Property Solutions Ltd | Real estate | 2025 |
| MLC Building Limited | Construction | 2021 |
| MLD Rigging Limited | Information & communication | 2025 |
| MLH Power System Ltd | Manufacturing | 2026 |
| MLP Management Systems Limited | Professional & scientific | 2017 |
| MLS Business Consultancy Limited | Professional & scientific | 2009 |
| MLS Development Ltd | Administrative & support | 2016 |
| MLS22 Ltd | Construction | 2021 |
| Mlynski Ltd | Education | 2025 |
| MM Building Services (Sheffield) Ltd | Construction | 2007 |
| MM Dolor Ltd | Wholesale & retail | 2021 |
| MM Electrical Contracting Limited | Construction | 2013 |
| MM Management International Ltd | Professional & scientific | 2017 |
| MMJ Property Management Ltd | Real estate | 2024 |
| MMK Windows (Rotherham) Ltd | Manufacturing | 2014 |
| MN Travel Ltd | Transport & logistics | 2024 |
| Mnas Properties Ltd | Real estate | 2023 |
| MO Fire Safety Limited | Professional & scientific | 2018 |
| Mobile Geekz Ltd | Wholesale & retail | 2025 |
| Mobile Opticians Limited | Health & social care | 2006 |
| Mobile Towbars 2U Limited | Wholesale & retail | 2024 |
| Mobile Tyrez Ltd | Wholesale & retail | 2026 |
| Mobipartner Ltd | Administrative & support | 2015 |
| Mocohan Line Ltd | Transport & logistics | 2023 |
| Modulus Precision Software Ltd | Information & communication | 2015 |
| Modura Doors Limited | Manufacturing | 2025 |
| Mogul Traditional Foods Limited | Extraterritorial | 2004 |
| Mohamed K Ahmed’S Ltd | Health & social care | 2026 |
| Mohammed Azeem Riaz Limited | Other services | 2018 |
| Mohammed Umer Sabir Ltd | Wholesale & retail | 2022 |
| Mohkam Group Ltd | Financial services | 2025 |
| Moldovan Motors Limited | Wholesale & retail | 2021 |
| MOMENTA3 Consulting Limited | Professional & scientific | 2020 |
| Momentum 81 Ltd | Information & communication | 2018 |
| Monaco's Mini Market Ltd | Wholesale & retail | 2025 |
| Mona’S Munchkins Limited | Health & social care | 2025 |
| Mondial Exhibitions Ltd | Administrative & support | 2014 |
| Monetizer Ltd | Professional & scientific | 2015 |
| Money Tree Accountancy Limited | Extraterritorial | 2016 |
| Monkey Fabrications Ltd | Manufacturing | 2023 |
| Monkwood 2020 Ltd | Hospitality | 2018 |
| Mono Malo Ltd | Hospitality | 2025 |
| Monochrome Corporate Finance Limited | Professional & scientific | 2019 |
| Monster Mesh Limited | Manufacturing | 2018 |
| Monster Recovery Service & Storage Ltd | Transport & logistics | 2025 |
| Monster Recovery Service Ltd | Wholesale & retail | 2023 |
| Montgomery Hall Enterprises Limited | Health & social care | 2001 |
| Monto Utilities Limited | Construction | 2008 |
| Monza Investments Limited | Professional & scientific | 2016 |
| Moojal Ltd | Wholesale & retail | 2025 |
| Moon Delicious Limited | Hospitality | 2024 |
| Moon&Star Wholesale Ltd | Wholesale & retail | 2023 |
| Moonies Ltd | Hospitality | 2019 |