| Mount Grain Ltd | Wholesale & retail | 2024 |
| Mount Pleasant Developments Ltd | Real estate | 2026 |
| Mount Pleasant Lane Limited | Construction | 2013 |
| Mount Rose UK Private Ltd | Hospitality | 2019 |
| Mount Zion Prayer Intercessory Network Ltd | Other services | 2018 |
| Mountain View Estate Agents Ltd | Real estate | 2012 |
| Mountgold Investment LLP | | 2026 |
| Mountmill London Limited | Other services | 2014 |
| Moutaber Ltd | Wholesale & retail | 2025 |
| MOV Builder Ltd | Construction | 2024 |
| Move First Limited | Real estate | 2009 |
| Move Mentor CIC | Education | 2025 |
| Move Mentor London Limited | Transport & logistics | 2025 |
| Movecore Ltd | Transport & logistics | 2026 |
| Movein Estates Ltd | Households | 2024 |
| Moveitservices Ltd | Transport & logistics | 2026 |
| Moves 4 YOU Ltd | Transport & logistics | 2021 |
| Movie Assist Security Ltd | Administrative & support | 2024 |
| Mowara Ltd | Wholesale & retail | 2022 |
| Moxels Limited | Information & communication | 2014 |
| Moya Meals Ltd | Hospitality | 2025 |
| Moyo Limited | Manufacturing | 2018 |
| Mozid Tutors Limited | Education | 2025 |
| MP Executive Travel Ltd | Transport & logistics | 2019 |
| MP Scaffolding Solutions Ltd | Construction | 2024 |
| Mpas North Ltd | Real estate | 2024 |
| MPD Forever Ltd | Construction | 2025 |
| MPE Security Limited | Administrative & support | 2024 |
| MPG Builders Ltd | Construction | 2024 |
| Mpgroundwork Ltd | Construction | 2015 |
| MPK PVT Ltd | Wholesale & retail | 2026 |
| MPK Quantity Surveyors Limited | Professional & scientific | 2011 |
| MPL Care Homes Limited | Health & social care | 2005 |
| MPM Drylining Services Ltd | Construction | 2025 |
| MPR Ventilation Ltd | Construction | 2015 |
| MPV Business Ltd | Construction | 2026 |
| MQ Accountants Limited | Professional & scientific | 2016 |
| MQ Courier Services Ltd | Transport & logistics | 2021 |
| MQH Trading Ltd | Professional & scientific | 2025 |
| MR Associates & Legal Services Ltd | Professional & scientific | 2025 |
| MR BEE Ltd | Wholesale & retail | 2025 |
| MR Budget Finds Limited | Wholesale & retail | 2026 |
| MR Chicken Ltd | Hospitality | 2020 |
| MR Chippy of Grove Park Ltd | Manufacturing | 2022 |
| MR Coding Limited | Wholesale & retail | 2025 |
| MR Desserts Ltd | Wholesale & retail | 2018 |
| MR Electrician Ltd | Construction | 2021 |
| MR Green’S Fresh Fruits and Vegetables Ltd | Wholesale & retail | 2025 |
| MR House Real Estate Ltd | Real estate | 2021 |
| MR Investments London Ltd | Real estate | 2018 |
| MR Jutley Ltd | Real estate | 2019 |
| MR Karak Limited | Hospitality | 2023 |
| MR Mayfair Properties Limited | Real estate | 2019 |
| MR PAL Group Limited | Wholesale & retail | 2024 |
| MR Real Estate Group Limited | Real estate | 2026 |
| MR Recycle Ltd | Water & waste | 2026 |
| MR SAT Kebab Ltd | Real estate | 2026 |
| MR Specialist Ltd | Professional & scientific | 2017 |
| MR Trading International Limited | Wholesale & retail | 2017 |
| MR Vendor Ltd | Wholesale & retail | 2021 |
| MR. Export Ltd | Transport & logistics | 2025 |
| MR. Voltage Electrical Services Ltd | Construction | 2022 |
| MR36822 Ltd | Information & communication | 2014 |
| Mrali Ltd | Information & communication | 2011 |
| MRC Facilities Ltd | Wholesale & retail | 2015 |
| MRC London UK Investments Limited | Real estate | 2013 |
| Mrcr Properties Limited | Real estate | 2016 |
| Mrct Consulting Limited | Information & communication | 2017 |
| Mrecig Limited | Wholesale & retail | 2018 |
| Mrei Group Ltd | Real estate | 2023 |
| Mrep CLO Limited | Extraterritorial | 2020 |
| MRH Contractors Limited | Other services | 2018 |
| MRH Pharma Ltd | Wholesale & retail | 2023 |
| MRI (U.K) Limited | Households | 2021 |
| MRI Today Ltd | Health & social care | 2026 |
| MRK Solutions Ltd | Transport & logistics | 2014 |
| MRN Foods Ltd | Wholesale & retail | 2025 |
| Mrnk Enterprsis Limited | Wholesale & retail | 2025 |
| MRP Building Services Ltd | Construction | 2009 |
| MRQ Consultancy Ltd | Administrative & support | 2019 |
| MRQ Dental Solutions Ltd | Health & social care | 2024 |
| MRS Meyer Ltd | Professional & scientific | 2018 |
| MRS Security Ltd | Administrative & support | 2024 |
| MRS Trio Estates Ltd | Real estate | 2022 |
| MRS Trio Limited | Hospitality | 2018 |
| MRS Trio Two Ltd | Hospitality | 2022 |
| MRS Whippy Time Ltd | Hospitality | 2024 |
| Mrtg Solutions Ltd | Financial services | 2023 |
| MS & an Property Ltd | Real estate | 2018 |
| MS & HK Holdings Limited | Real estate | 2023 |
| MS & P Limited | Real estate | 2025 |
| MS Accountants Limited | Professional & scientific | 2022 |
| MS Appliances Repair Limited | Other services | 2025 |
| MS Auto Travel Ltd | Hospitality | 2025 |
| MS BAL Construction Limited | Construction | 2023 |
| MS Build Ltd | Construction | 2025 |
| MS Business Services Limited | Construction | 2019 |
| MS Catering & Events Ltd | Hospitality | 2020 |
| MS Cleaning & Removals Ltd | Transport & logistics | 2019 |
| MS Events Limited | Hospitality | 2012 |