| Mema Home Ltd | Extraterritorial | 2024 |
| Mema Skin & Wellness Clinic Ltd | Other services | 2024 |
| Mema Skin Academy Ltd | Extraterritorial | 2024 |
| Memap Homes SL Ltd | Real estate | 2025 |
| Memtech Ltd | Construction | 1997 |
| Mendip Group Ltd | Construction | 2024 |
| Mere Park Management Company Limited | Real estate | 1989 |
| Meredith Estates Limited | Real estate | 2015 |
| Meridian Solutions (Global) Limited | Professional & scientific | 2016 |
| Merlinus Studios Limited | Information & communication | 2020 |
| MFW Manchester Ltd | Wholesale & retail | 2026 |
| Mhps (NW) Ltd | Construction | 2021 |
| MIA Swim Limited | Wholesale & retail | 2022 |
| Michael James Knowles & Co Ltd | Professional & scientific | 2010 |
| Micklefine Ltd | Hospitality | 2003 |
| Microlife UK Limited | Information & communication | 1985 |
| Migrant Journal Press Ltd | Information & communication | 2016 |
| Miika Ltd | Professional & scientific | 2019 |
| Mila Virtual Assistants Ltd | Administrative & support | 2026 |
| Milgate Ltd | Manufacturing | 2018 |
| Mill Brook (Catterall) Limited | Households | 1999 |
| Mill Commercial Cleaning Ltd | Administrative & support | 2017 |
| Mill Farm Rental Limited | Real estate | 2014 |
| Mill Farm Ventures Limited | Arts & recreation | 2012 |
| Millbrook Investments Limited | Real estate | 2016 |
| Milly Renewables Ltd | Other services | 2025 |
| Mirrie Dancer Cafe Limited | Wholesale & retail | 2022 |
| MJ Sooriya Ltd | Real estate | 2026 |
| MJS Products Ltd | Wholesale & retail | 2024 |
| MK Wigan Ltd | Other services | 2019 |
| Mlgc Media Ltd | Professional & scientific | 2025 |
| MLT Engineering Services Ltd | Construction | 2023 |
| MMC Media International Ltd | Information & communication | 2020 |
| MMC Media Worldwide Ltd | Information & communication | 2025 |
| Mmpath Ltd | Health & social care | 2013 |
| Mncj Care Services Limited | Health & social care | 2025 |
| Mobile Autocare Solutions Ltd | Wholesale & retail | 2020 |
| Mode Hotel Ltd | Hospitality | 2015 |
| Modeii Ltd | Information & communication | 2009 |
| Modern Classics Lytham Ltd | Wholesale & retail | 2021 |
| Modicum Limited | Professional & scientific | 2013 |
| Modup Ecobuild Ltd | Professional & scientific | 2021 |
| Molly the Mobile GIN Bar Ltd | Wholesale & retail | 2018 |
| Momente Consulting Limited | Professional & scientific | 2025 |
| Moments Travel and Adventures Ltd | Administrative & support | 2024 |
| Montclair Properties Ltd | Real estate | 2020 |
| Moore's Digital Ltd | Professional & scientific | 2025 |
| Moorfield of Lancashire Limited | Manufacturing | 1987 |
| Moorland Management Company Limited | Households | 2003 |
| Moreton Partners Limited | Professional & scientific | 2017 |
| Morgan Heating & Plumbing Solutions Limited | Construction | 2016 |
| Mortgage Options (UK) Ltd | Financial services | 2002 |
| Mortgages by Lindsay Warbrick Ltd | Financial services | 2021 |
| Mosaic LDS Ltd | Professional & scientific | 2023 |
| Motion Injury Clinic Ltd | Health & social care | 2019 |
| Motorlands Motorhomes Limited | Wholesale & retail | 2013 |
| Mottershead IT Services Ltd | Other services | 2021 |
| Move-Nest Property Limited | Professional & scientific | 2025 |
| Moveit Associates Limited | Information & communication | 2011 |
| Mowbray Property Investments Limited | Real estate | 2020 |
| MR Loud Trousers Limited | Hospitality | 2024 |
| Mramm Ltd | Hospitality | 2025 |
| Mrio Distribution Ltd | Wholesale & retail | 2026 |
| MSF (PV) Limited | Extraterritorial | 2014 |
| MT Clothing Limited | Wholesale & retail | 2012 |
| Mtex (UK) Limited | Manufacturing | 2006 |
| Muhtar Restaurants Limited | Hospitality | 2024 |
| Mulberry Chase Properties Ltd | Real estate | 2022 |
| Mulligan Family Holdings Ltd | Financial services | 2021 |
| Mulligan Nurseries Ltd | Health & social care | 2023 |
| Multipotentialiteco Ltd | Health & social care | 2024 |
| Multistage Ltd | Real estate | 2003 |
| Murano House Properties Ltd | Real estate | 2024 |
| Muscari Consulting Limited | Information & communication | 2016 |
| Muscari Limited | Hospitality | 2016 |
| Music Time Tuition Limited | Education | 2016 |
| MVW Consulting Ltd | Information & communication | 2019 |
| MW Access Solutions Limited | Construction | 2022 |
| My EPC Limited | Professional & scientific | 2020 |
| My Leads Group Limited | Information & communication | 2019 |
| My Suites Ltd | Hospitality | 2017 |
| My Wish Properties Ltd | Real estate | 2023 |
| Mythop Management Company Limited | Households | 2021 |
| MZK Limited | Information & communication | 2009 |
| N and M Halliwell Ltd | Wholesale & retail | 2000 |
| Namaste Herbal Healing Ltd | Health & social care | 2024 |
| Naomi Digital Ltd | Professional & scientific | 2025 |
| Nasumpsychology Ltd | Other services | 2022 |
| Natana Ltd | Financial services | 2022 |
| National Anpr Parking Management Ltd | Other services | 2023 |
| National Baby Sitting and Crèche Agency Ltd | Health & social care | 2019 |
| National Baby Sitting and Crèche Services Ltd | Health & social care | 2019 |
| Natures Health Limited | Wholesale & retail | 2009 |
| NAZ Pizza House Ltd | Hospitality | 2023 |
| NBB Holdings Limited | Financial services | 2024 |
| Near Future Limited | Financial services | 2016 |
| Neil Gallagher Ltd | Professional & scientific | 2022 |
| Neon Moon Limited | Wholesale & retail | 2014 |
| Neon Mountain Ltd | Information & communication | 2023 |
| NER Group Limited | Professional & scientific | 2021 |