| Morethanok Limited | Real estate | 2012 |
| Morfose Barbers Limited | Other services | 2017 |
| Morgan Global Impex Limited | Manufacturing | 2024 |
| Mori Japanese Ltd | Hospitality | 2017 |
| Mori Oriental Ltd | Wholesale & retail | 2018 |
| Morphic Property Management Ltd | Real estate | 2023 |
| Mortala IT Services Ltd | Information & communication | 2025 |
| Mortar Investments International Limited | Professional & scientific | 1992 |
| Mortar Investments UK Limited | Professional & scientific | 1992 |
| Mortar Slough Ltd | Real estate | 2025 |
| Mortel Meister UK Ltd | Administrative & support | 2019 |
| Mortgage Advice Agency Ltd | Financial services | 2016 |
| Mortgage Marvels Ltd | Financial services | 2023 |
| Mortgage Masters Financial Services Ltd | Financial services | 2024 |
| Mortgage Matters (Hayes) Limited | Financial services | 2018 |
| Mortgages & More (London) Ltd | Other services | 2009 |
| Mortgagez Limited | Financial services | 2018 |
| Mosor Transport Ltd | Transport & logistics | 2025 |
| Moss & Mist Limited | Information & communication | 2024 |
| Moss Building Works Ltd | Construction | 2026 |
| Mossquest Limited | Wholesale & retail | 1988 |
| MOT Mobile Ltd | Wholesale & retail | 2021 |
| Motas Workshop Ltd | Wholesale & retail | 2016 |
| Motec (SW) Limited | Wholesale & retail | 2012 |
| Motec Holdco Limited | Financial services | 2023 |
| Motec Propco Limited | Real estate | 2023 |
| Motherhood AID CIC | Education | 2023 |
| Mothernext Limited | Transport & logistics | 2024 |
| Moto Healthcare Staffing Limited | Administrative & support | 2021 |
| Motor Aspirations Limited | Wholesale & retail | 2017 |
| Motor Emergency Services Limited | Wholesale & retail | 2025 |
| Motor Passion Ltd | Arts & recreation | 2005 |
| Motor Trade Investment Ltd | Wholesale & retail | 2022 |
| Motor Vehicle Services Slough Ltd | Wholesale & retail | 2026 |
| Motorace Ltd | Wholesale & retail | 2023 |
| Motorcare MOT & Service Centre Limited | Wholesale & retail | 2010 |
| Motorec UK Ltd | Wholesale & retail | 2025 |
| Motormaze Limited | Wholesale & retail | 2021 |
| Motors ARE US Limited | Wholesale & retail | 2023 |
| Motorsource Group Ltd | Wholesale & retail | 2026 |
| Motorverse Ltd | Wholesale & retail | 2025 |
| Motorway Recovery Ltd | Transport & logistics | 2018 |
| Motorx Ltd | Wholesale & retail | 2023 |
| Moukam Ltd | Real estate | 2025 |
| Moultek Limited | Professional & scientific | 2009 |
| Mount Everest Scaffolding Ltd | Construction | 2014 |
| Mount West General Trading Ltd | Wholesale & retail | 2023 |
| Mountworks Limited | Wholesale & retail | 2025 |
| Mova Group 2024 Ltd | Hospitality | 2024 |
| Movantage Limited | Professional & scientific | 2013 |
| Move My Bags Ltd | Administrative & support | 2016 |
| Move..Ea Ltd | Real estate | 2022 |
| Moveair ICT Limited | Professional & scientific | 2016 |
| Movecraft Ltd | Transport & logistics | 2025 |
| Moveit Group Ltd | Transport & logistics | 2023 |
| Moveituk Limited | Transport & logistics | 2026 |
| Movemyrental Ltd | Transport & logistics | 2025 |
| Movers for Move Ltd | Transport & logistics | 2020 |
| Movexa Logistics Ltd | Wholesale & retail | 2026 |
| Movie Kitchens Limited | Administrative & support | 2023 |
| Mowasa Limited | Administrative & support | 2022 |
| MOX Online Ltd | Wholesale & retail | 2025 |
| Moxitech Ltd | Professional & scientific | 2022 |
| Moyelat Ventures Limited | Wholesale & retail | 2024 |
| Moztec Limited | Wholesale & retail | 2023 |
| MP Aesthetics PVT Limited | Health & social care | 2026 |
| MP Sets Ltd | Construction | 2015 |
| Mp&M Builders Ltd | Construction | 2020 |
| Mpha Consulting Ltd. | Education | 2019 |
| MPJ Electrical Ltd | Construction | 2017 |
| Mployedin UK Ltd | Information & communication | 2022 |
| MPM Flooring Limited | Construction | 2009 |
| MPS Management Services Ltd | Professional & scientific | 2020 |
| Mpsp Holdings Limited | Financial services | 2021 |
| MQ Cleaning Ltd | Administrative & support | 2023 |
| MQA Consulting Ltd | Information & communication | 2025 |
| MQB Services Ltd | Construction | 2021 |
| MQH Ltd | Real estate | 2019 |
| MQK Limited | Real estate | 2007 |
| MR Auto Traders Ltd | Wholesale & retail | 2026 |
| MR Autos & Electrical Ltd | Wholesale & retail | 2015 |
| MR Bamboo Limited | Wholesale & retail | 2024 |
| MR Browne Auto Diagnostics Ltd | Wholesale & retail | 2018 |
| MR Carpets & Flooring Limited | Construction | 2017 |
| MR COD Franchise Ltd | Hospitality | 2000 |
| MR COD GG Limited | Hospitality | 2022 |
| MR Deol Motors Limited | Wholesale & retail | 2024 |
| MR Education Consultancy Ltd | Education | 2019 |
| MR Enzo Hand Car Wash Limited | Other services | 2017 |
| MR Expert Carpet Cleaning Ltd | Other services | 2025 |
| MR GST Ltd | Transport & logistics | 2024 |
| MR Home Service Ltd | Administrative & support | 2026 |
| MR M a Baig Ltd | Wholesale & retail | 2018 |
| MR Maan Barber Ltd | Other services | 2025 |
| MR Mani Ltd | Wholesale & retail | 2025 |
| MR Pharma Enterprise Limited | Real estate | 2022 |
| MR SIR Limited | Information & communication | 2020 |
| MR T'S (Slough) Ltd | Hospitality | 2025 |
| MR TOW Limited | Wholesale & retail | 2020 |
| Mrakas Limited | Wholesale & retail | 2023 |