| Morpheus Lending Ltd | Financial services | 2023 |
| Morpheus Lending SPV1 Ltd | Financial services | 2024 |
| Morpheus Lending SPV2 Ltd | Financial services | 2024 |
| Morris Green Motors Limited | Wholesale & retail | 2010 |
| Morris Quality Bakers Limited | Manufacturing | 2018 |
| Morris’S of Coppull Limited | Financial services | 2020 |
| Mors Associates Limited | Professional & scientific | 2012 |
| Mortgage Experience Limited | Financial services | 2016 |
| Mosaic Investments Holdings Limited | Financial services | 2025 |
| Mosaic Media Solutions Ltd | Information & communication | 2013 |
| Mosaic Psychology Limited | Administrative & support | 2021 |
| Mosborough Lifts Limited | Manufacturing | 2011 |
| Moses Enterprises Limited | Hospitality | 2019 |
| Moss Aesthetics Ltd | Other services | 2022 |
| Motion Labs Limited | Manufacturing | 2025 |
| Motion Motor Company (NW) Ltd | Administrative & support | 2013 |
| Moto GB Limited | Wholesale & retail | 2000 |
| MOTO73 Ltd | Wholesale & retail | 1998 |
| Motor Chrome World Limited | Wholesale & retail | 2013 |
| Motor-Carbox Limited | Wholesale & retail | 2017 |
| Motorbike Hearse Ltd | Other services | 2021 |
| Motoring Made Easy Ltd | Transport & logistics | 2014 |
| Motorplus Limited | Financial services | 1995 |
| Motorsport Components Ltd | Manufacturing | 2017 |
| Motus Mechanics Ltd | Administrative & support | 2014 |
| Mountain Contracts Ltd | Construction | 2022 |
| Mountdale Construction Limited | Construction | 2020 |
| MOV Contractors Ltd | Construction | 2018 |
| Movendo Ltd | Information & communication | 2026 |
| MP Trading & Transport Ltd | Transport & logistics | 2020 |
| Mpeace Limited | Real estate | 1973 |
| Mpeng Limited | Professional & scientific | 2017 |
| MPN Building and Civil Engineering Ltd | Construction | 2021 |
| Mpover Academy Ltd | Education | 2025 |
| MPR Commercial Lettings Limited | Real estate | 2018 |
| MR Chips (Southport) Ltd | Wholesale & retail | 2020 |
| MR Meech Clothing Ltd | Wholesale & retail | 2018 |
| MRB Training Limited | Administrative & support | 2011 |
| MRB Witness Services Limited | Administrative & support | 2020 |
| MRC (NW) Ltd | Real estate | 2010 |
| MRC (NW) Properties Ltd | Real estate | 2016 |
| MRC Productions Limited | Professional & scientific | 2019 |
| Mrhaque Pharma Ltd | Health & social care | 2025 |
| MRM Building, Maintenance & Electrical Limited | Construction | 2018 |
| MRN Engineering Solutions Ltd | Professional & scientific | 2014 |
| MS Family Shopper Ltd | Wholesale & retail | 2025 |
| MS Mcginty Consultancy Ltd | Professional & scientific | 2020 |
| MSA Chorley Ltd | Arts & recreation | 2019 |
| MSA Fitness Limited | Education | 2019 |
| MSA Stockport Limited | Arts & recreation | 2015 |
| MSB Couriers Limited | Transport & logistics | 2015 |
| Mserv Global Limited | Professional & scientific | 2009 |
| MSJ Consultancy Service Ltd | Other services | 2023 |
| MSK Management Ltd | Real estate | 2025 |
| Msms Investments Ltd | Financial services | 2023 |
| MSO Driving & Bowling Green Services Ltd | Education | 2010 |
| Msop Nominees Limited | Financial services | 2023 |
| MT Interiors Limited | Professional & scientific | 2015 |
| MTA London Construction Ltd | Construction | 2010 |
| MTC Construction (North West) Ltd | Construction | 2017 |
| MTG Consultancy Ltd | Professional & scientific | 2018 |
| MTT Group Limited | Professional & scientific | 2006 |
| MTT Holdings Limited | Financial services | 2011 |
| MTW Corporate Services Ltd | Financial services | 2018 |
| MU Logistics Ltd | Other services | 2018 |
| Much Greater Than Ltd | Information & communication | 2023 |
| Mulberry Maids (EB) Limited | Administrative & support | 2017 |
| Mulberry Moon Limited | Wholesale & retail | 2015 |
| Mulla Property Management Limited | Real estate | 2018 |
| Multi Health Specialists Ltd | Health & social care | 2011 |
| Multi Trades Group Ltd | Construction | 2020 |
| Multiclean Supplies Ltd | Administrative & support | 2015 |
| Multiflor Limited | Construction | 2012 |
| Munch Time Pizza Limited | Hospitality | 2015 |
| Munday & Pearse Property Group Ltd | Real estate | 2025 |
| Munro-James Ltd | Professional & scientific | 2015 |
| Munshi Allen ST Ltd | Real estate | 2021 |
| Munshi Canterbury Ltd | Real estate | 2018 |
| Munshi Holdings (UK) Ltd | Real estate | 2016 |
| Murphy GAS Ltd | Construction | 2026 |
| Murray - Cooper Limited | Construction | 2012 |
| Muse Luxe Ltd | Wholesale & retail | 2025 |
| Mush Mountain Ltd | Wholesale & retail | 2025 |
| Mushroom Growing Supplies Limited | Wholesale & retail | 2024 |
| Mussoorie Holdings Ltd | Financial services | 2025 |
| MV and Sons Holdings Ltd | Hospitality | 2017 |
| MV Comms Ltd | Information & communication | 2012 |
| MV Group Inc Ltd | Hospitality | 2024 |
| MWD Consultants Limited | Professional & scientific | 2020 |
| MWS Surveying Ltd | Construction | 2022 |
| My Baby Enterprises Ltd | Health & social care | 2015 |
| My Clear Accounts Limited | Professional & scientific | 2016 |
| My Clinic Consultant Ltd | Professional & scientific | 2024 |
| My Digital Wardrobe Ltd | Wholesale & retail | 2025 |
| My DNA LAB Limited | Health & social care | 2016 |
| My Health Assistant Ltd | Information & communication | 2021 |
| My Office Space Limited | Administrative & support | 2017 |
| My Online Pet Store Ltd | Wholesale & retail | 2022 |
| My Pet Physio & Hydro Limited | Professional & scientific | 2020 |
| My Pretty Little Gift Ltd | Wholesale & retail | 2010 |