| Mitch Sports Management Limited | Arts & recreation | 2025 |
| Mitchell Health Consultancy Ltd | Health & social care | 2025 |
| Mitchell Kelly Ltd | Professional & scientific | 2007 |
| Miura Technologies Limited | Information & communication | 2019 |
| Miwest Services Limited | Manufacturing | 2019 |
| Mizar Design Limited | Administrative & support | 2009 |
| MJ Commercial Property Limited | Administrative & support | 2025 |
| MJ Higgins Property Services Limited | Construction | 2026 |
| MJ Joinery and Double Glazing Ltd | Construction | 2019 |
| MJ Sanders Consultancy Limited | Extraterritorial | 2025 |
| MJ Thompson Consultants Limited | Administrative & support | 2007 |
| MJA Enterprise Group Ltd | Wholesale & retail | 2024 |
| MJB DV Limited | Professional & scientific | 2016 |
| MJB Management Services Ltd. | Professional & scientific | 2004 |
| MJC Leadership Limited | Professional & scientific | 2008 |
| Mjdc Developments Limited | Real estate | 2014 |
| MJGTRADING23 Ltd | Wholesale & retail | 2023 |
| MJK Capital Limited | Financial services | 2017 |
| MJK Property Ltd | Real estate | 2002 |
| MJN Consultancy Ltd | Professional & scientific | 2017 |
| Mjolnir Developments Ltd | Real estate | 2022 |
| MJR Hairdressing Limited | Other services | 2012 |
| MK Records Ltd | Information & communication | 2022 |
| MK Wallasey Barber Limited | Other services | 2025 |
| Mkjd Solutions Ltd | Professional & scientific | 2012 |
| ML Marketing Ltd | Professional & scientific | 2016 |
| MLC Templating Limited | Professional & scientific | 2025 |
| MM Insulation Ltd | Construction | 2026 |
| MMA Wirral Property Ltd | Real estate | 2024 |
| MMC NDT Limited | Professional & scientific | 2015 |
| MMC Transfers Ltd | Extraterritorial | 2025 |
| Mmeyou Ltd | Information & communication | 2018 |
| Mmky Limited | Health & social care | 2024 |
| MNK Windows Limited | Construction | 2023 |
| MNS Premium Properties Ltd | Real estate | 2023 |
| Moam Services Ltd | Professional & scientific | 2023 |
| Mobile CPX Limited | Health & social care | 2012 |
| Modern Launderette Ltd | Other services | 2026 |
| Modern Streets Limited | Wholesale & retail | 2022 |
| Modified Car Parts and Accessories Ltd | Extraterritorial | 2010 |
| Modular Management Limited | Administrative & support | 2018 |
| Modwell Development Ltd | Real estate | 2025 |
| Mojito Ltd | Administrative & support | 2008 |
| Molby the Label Ltd | Wholesale & retail | 2020 |
| Molloy & SON Landscaping & Surfacing Ltd | Administrative & support | 2024 |
| Molly Harvey Global Limited | Professional & scientific | 2009 |
| Molmagan Ltd | Real estate | 2021 |
| Moltenfrog Ltd | Information & communication | 2016 |
| Momentum Growth Ltd | Information & communication | 2024 |
| Momentum Personal Solutions Ltd | Administrative & support | 2021 |
| Momina Tech Ltd | Administrative & support | 2021 |
| Monday Studios Ltd | Arts & recreation | 2026 |
| Moneta Solutions Limited | Information & communication | 2017 |
| Moonbeam Yoga Wirral With Hannah Ltd | Arts & recreation | 2019 |
| Moonfrog Events Ltd | Arts & recreation | 2021 |
| Moonlight Stays SA Ltd | Hospitality | 2026 |
| Moorfield Enterprises Ltd | Other services | 2024 |
| Moose Incorporated Limited | Health & social care | 2023 |
| Moparts Limited | Professional & scientific | 1928 |
| More Access Ltd | Administrative & support | 2024 |
| More Drinks Ltd | Administrative & support | 2024 |
| More Taste, Less Speed Limited | Wholesale & retail | 2022 |
| More Than Coaching Ltd | Administrative & support | 2016 |
| Morello Consultancy Limited | Information & communication | 2024 |
| Moreton Carpet Centre Limited | Wholesale & retail | 2009 |
| Moreton Community Centre Ltd | Other services | 2010 |
| Moreton Hand Car Wash Ltd | Wholesale & retail | 2025 |
| Moreton Marble and Granite Limited | Construction | 2021 |
| Moreton Nails Ltd | Other services | 2026 |
| Moreton Nice Barber Ltd | Other services | 2021 |
| Moreton Shawarma Ltd | Hospitality | 2025 |
| Moreton Store Ltd | Wholesale & retail | 2026 |
| Moreton Tiles Limited | Wholesale & retail | 2013 |
| Moretonmotorsport Ltd | Wholesale & retail | 2023 |
| Morheat Ltd | Construction | 2021 |
| Morland Property Solutions Ltd | Construction | 2024 |
| Morris Jones and SON Carpets Limited | Wholesale & retail | 1985 |
| Morrish Technical Limited | Professional & scientific | 2023 |
| Morrison Daly Consulting Ltd | Professional & scientific | 2022 |
| Mortgageneeds.Info Limited | Financial services | 2005 |
| Morva Lodge Management Company Limited | Households | 1991 |
| Mosaic Associates Limited | Professional & scientific | 2007 |
| Mosopaige Limited | Information & communication | 2025 |
| Moston Developments Ltd | Construction | 2020 |
| Mostyn House Freehold Management Company Limited | Households | 2014 |
| Mother India (Hoylake) Ltd | Hospitality | 2021 |
| Motion Events Catering Limited | Hospitality | 2023 |
| Motivating Minds Ltd | Administrative & support | 2023 |
| Motorhome and Campervan Newbies Ltd | Wholesale & retail | 2026 |
| Motus Consultancy Ltd | Information & communication | 2025 |
| Mount Court, Heswall Management Company Limited | Households | 2009 |
| Mount Invest Ltd | Construction | 2019 |
| Mountain Forty Nine Ltd | Information & communication | 2023 |
| Movement & Bloom CIC | Education | 2020 |
| Movement Matters Community CIC | Health & social care | 2025 |
| Movement Matters Hub Ltd | Education | 2025 |
| Movement Technology Logistics Limited | Transport & logistics | 2026 |
| Moverley Marine Ltd | Transport & logistics | 2023 |
| Moving Soon Limited | Information & communication | 2010 |
| MP Bespoke Roofing Ltd | Construction | 2022 |