| Mersey View Management Company Limited | Households | 2025 |
| Mersey View Property Investments Ltd | Real estate | 2025 |
| Mersey Waste (NW) Limited | Water & waste | 2018 |
| Merseymoversmnvs Ltd | Transport & logistics | 2026 |
| Merseysec Ltd | Administrative & support | 2019 |
| Merseyside Car Repairs Limited | Wholesale & retail | 2016 |
| Merseyside Community Chaplaincy CIC | Health & social care | 2025 |
| Merseyside Eats Group PVT Ltd | Wholesale & retail | 2025 |
| Merseyside Mental Health Collective CIC | Health & social care | 2026 |
| Mertystore Ltd | Wholesale & retail | 2025 |
| MF Services and Consulting Ltd | Information & communication | 2026 |
| Mform Visualisation Limited | Professional & scientific | 2018 |
| Mgcomms Ltd | Information & communication | 2023 |
| MGM Projects Ltd | Construction | 2021 |
| MH Consultancy Northwest Ltd | Financial services | 2026 |
| MH Relief Chef Limited | Hospitality | 2019 |
| Miall & Barnes Limited | Construction | 2021 |
| Miarlo Construction & Developments Limited | Construction | 2019 |
| Miarlo Properties Limited | Real estate | 2019 |
| MIB Managing International Borders Ltd | Professional & scientific | 2022 |
| Michael Gilfoyle Limited | Health & social care | 2021 |
| Mieonx Ltd | Wholesale & retail | 2026 |
| Mike Walker Transport Ltd | Transport & logistics | 2018 |
| Miketer Car Sales Ltd | Wholesale & retail | 2024 |
| Mikey O'Brien Gardening Limited | Administrative & support | 2024 |
| MILES2GO Ltd | Professional & scientific | 2011 |
| Mill Talent Ltd | Professional & scientific | 2026 |
| Millhey Court Management Company Limited | Households | 2001 |
| Millthwaite Court Management Limited | Households | 1971 |
| Minchella's Limited | Professional & scientific | 2016 |
| Mindful Training Ltd | Education | 2018 |
| Mindhaus Video Ltd | Information & communication | 2023 |
| Minkad Limited | Administrative & support | 2018 |
| Mitauk Ltd | Professional & scientific | 2024 |
| Mitchells Property Ventures Ltd | Real estate | 2024 |
| Mixvale Limited | Real estate | 1991 |
| MJB Consultancy Services Limited | Professional & scientific | 2023 |
| MJW Installations Ltd | Construction | 2025 |
| MK Barber London Ltd | Other services | 2019 |
| MK1 Design Limited | Professional & scientific | 2023 |
| Mkb-Physio Ltd | Health & social care | 2013 |
| ML Light House Limited | Real estate | 2025 |
| MM Architectural Services Ltd | Professional & scientific | 2018 |
| MM Fast Track Ltd | Transport & logistics | 2024 |
| Mmoniemang Ltd | Health & social care | 2025 |
| MND Vacuum & Cleaning Ltd | Administrative & support | 2025 |
| Mobile Security Inspectors Ltd | Administrative & support | 2025 |
| Mohra Wallasey Management Ltd | Hospitality | 2025 |
| Mole Group Utilities Ltd | Construction | 2018 |
| Molloys Garden Center Ltd | Wholesale & retail | 2026 |
| MON Ceramics Ltd | Arts & recreation | 2013 |
| Moneysworth (Wirral) Limited | Wholesale & retail | 2003 |
| Montaña Atavío Ltd | Wholesale & retail | 2024 |
| Montpellier Court Management Services Ltd | Households | 2020 |
| Mooway Music Ltd | Education | 2010 |
| More of YOU Coaching Limited | Education | 2016 |
| Motor Factors Wallasey Ltd | Manufacturing | 2025 |
| Mount Court Management (Wallasey) Limited | Households | 1973 |
| Mount Pleasant Flat Management Company Limited | Households | 2003 |
| Mountwood Building Management Limited | Households | 2016 |
| MPC Holdings Wirral Ltd | Real estate | 2026 |
| MPF Technical Solutions Limited | Information & communication | 2026 |
| MR Blue Convenience Store Ltd | Wholesale & retail | 2024 |
| MR Blue Vape Shop Ltd | Wholesale & retail | 2026 |
| MSA First Ltd | Hospitality | 2025 |
| MSB Property Management Limited | Real estate | 2021 |
| MTV Property Consultancy Services Ltd | Real estate | 2016 |
| Multelec Electrical Limited | Construction | 2013 |
| Music IS NOW Pubs Limited | Hospitality | 2025 |
| Musicteam Limited | Education | 2009 |
| My Legal HR Limited | Administrative & support | 2023 |
| My OH My Ltd | Professional & scientific | 2019 |
| MYTH33 Ltd | Extraterritorial | 2019 |
| N J P Building Services Ltd | Construction | 2012 |
| N Smith Groundworks Ltd | Other services | 2020 |
| N. R. Joinery Contractors Ltd | Construction | 2010 |
| N5 Studios Ltd | Professional & scientific | 2017 |
| Naptran Limited | Transport & logistics | 2016 |
| NAS Pensions Consultancy Ltd | Professional & scientific | 2019 |
| Natural Pet Shop Ltd | Wholesale & retail | 2024 |
| Natural Ranks (Liverpool) Limited | Professional & scientific | 2009 |
| Nautilus Trustees Limited | Other services | 1984 |
| Naymak Ltd | Households | 2024 |
| NB Wirral Properties Ltd | Real estate | 2021 |
| Needle in the Groove Ltd | Wholesale & retail | 2025 |
| Neil & Louise Ltd | Real estate | 2024 |
| Nelmani Ltd | Wholesale & retail | 2021 |
| Nenna Plumbing and Heating Ltd | Construction | 2022 |
| NEP Technical Services Ltd | Construction | 2018 |
| Nettlehill Management Company Limited | Households | 1997 |
| Neurevo Digital Health Ltd | Information & communication | 2025 |
| New Brighton Arts Club Community Interest Company | Hospitality | 2024 |
| New Brighton Creative Futures CIC | Arts & recreation | 2025 |
| New Brighton Cricket and Bowling Club Limited | Arts & recreation | 1891 |
| New Brighton Day Nursery C.I.C. | Education | 2013 |
| New Brighton Development Company Limited | Construction | 2006 |
| New Brighton Fuels Limited | Other services | 2012 |
| New Brighton Jazz Bars Limited | Hospitality | 2026 |
| New Brighton Partnership CIC | Administrative & support | 2025 |
| New Hope Vets Ltd | Professional & scientific | 2022 |