| Media for YOU Ltd | Information & communication | 2024 |
| Media Mechanics Ltd | Information & communication | 2023 |
| Medibiosense Ltd | Information & communication | 2015 |
| Medical Care Pro Ltd | Other services | 2018 |
| Medical Services D-E-B Ltd | Health & social care | 2019 |
| Medico Advisory Ltd | Professional & scientific | 2021 |
| Medico Claims Limited | Health & social care | 2019 |
| Medico-Legal Assessment Limited | Health & social care | 2016 |
| Medicscover Ltd | Health & social care | 2020 |
| Mediderm Aesthetics Ltd | Administrative & support | 2024 |
| Medio Solutions Limited | Professional & scientific | 2023 |
| Medipharm Consultants Limited | Health & social care | 2007 |
| Mediplay Ltd | Wholesale & retail | 2025 |
| Medisource Services Ltd | Real estate | 2007 |
| Medispares Express Limited | Wholesale & retail | 2025 |
| Medley Farms Limited | Agriculture & fishing | 2025 |
| Medrock Training Ltd | Health & social care | 2005 |
| Medusa Hair Creations Ltd | Other services | 2022 |
| Medved Limited | Financial services | 2014 |
| Meenaghan & SON Civil Engineers Ltd | Construction | 2018 |
| Meet ME @ Ltd | Hospitality | 2018 |
| Meetyourfan Ltd | Information & communication | 2025 |
| Mega Export Ltd | Wholesale & retail | 2017 |
| Mega Import Ltd | Wholesale & retail | 2017 |
| Mega Market (Copley) Ltd | Wholesale & retail | 2022 |
| Mega Meal Limited | Hospitality | 2026 |
| Mega Super Mart Ltd | Wholesale & retail | 2025 |
| Mega Trading (PVT) Ltd | Wholesale & retail | 2017 |
| Mega Volt Installations Ltd | Construction | 2025 |
| Megenvest Limited | Hospitality | 1997 |
| MEH Property Services Ltd | Construction | 2025 |
| Mehfil Spice 2026 Limited | Hospitality | 2026 |
| Meiders Dellentechnik Holding Limited | Financial services | 2026 |
| Meine Holdings Limited | Financial services | 2025 |
| Meine Investments Limited | Information & communication | 2021 |
| Meine Limited | Real estate | 2025 |
| Mejb Signalling Services Ltd | Construction | 2020 |
| Mejk Transport Ltd | Administrative & support | 2013 |
| Meklar Manufacturing Ltd | Manufacturing | 2025 |
| Meklar UK Limited | Administrative & support | 2010 |
| MEL & NOK Limited | Transport & logistics | 2013 |
| Meliora KBB Limited | Construction | 2017 |
| Melita Bees Holding Limited | Financial services | 2020 |
| Mell Developments Ltd | Construction | 2003 |
| Mellor Properties NO. 1 Limited | Professional & scientific | 2006 |
| Mellor Properties NO. 2 Limited | Professional & scientific | 2006 |
| Mellors Fish Bar Limited | Hospitality | 2018 |
| Melody Maison Limited | Wholesale & retail | 2009 |
| Melody Maison Warehousing Limited | Extraterritorial | 2025 |
| Melodymagix Ltd | Manufacturing | 2025 |
| Melt Leisure Limited | Hospitality | 2024 |
| Melton Developments (Doncaster) Limited | Construction | 1997 |
| Melv Rail Limited | Professional & scientific | 2014 |
| MEM Pizza Ltd | Hospitality | 2024 |
| Membergate Limited | Other services | 2015 |
| Memis Pizza Limited | Hospitality | 2020 |
| Memo Cafe Ltd | Hospitality | 2026 |
| Memolu Ltd | Professional & scientific | 2019 |
| Memories Givers Ltd | Wholesale & retail | 2024 |
| Menopause Naturally Limited | Health & social care | 2026 |
| Mens Clothes Discount Codes Ltd | Extraterritorial | 2019 |
| Mensahsah Ltd | Real estate | 2025 |
| Mental Health FC CIC | Arts & recreation | 2023 |
| Mental Health Legal Representation Limited | Professional & scientific | 2013 |
| Mental Truckers Ltd | Wholesale & retail | 2025 |
| Menu Brazil Ltd | Hospitality | 2020 |
| Menzone Barbers Limited | Other services | 2016 |
| MEP Properties Ltd | Construction | 2026 |
| Merc Express Ltd | Transport & logistics | 2021 |
| Mercatorius Melius Ltd | Professional & scientific | 2023 |
| Mercatura Limited | Financial services | 2022 |
| Merchant of Menace Ltd | Wholesale & retail | 2025 |
| Merchant Pagan Limited | Information & communication | 1999 |
| Merchant Way Bakery Limited | Manufacturing | 2014 |
| Mercia Waste Management Limited | Energy | 1998 |
| Merciful GOD Ministries | Other services | 2010 |
| Mercilicious Group Limited | Wholesale & retail | 2025 |
| Mercova Group Holdings Limited | Professional & scientific | 2025 |
| Mercova Holdings Limited | Professional & scientific | 2025 |
| Mercova Limited | Professional & scientific | 2025 |
| Mercury Construction Limited | Construction | 2015 |
| Mercury Executive Cabs Ltd | Transport & logistics | 2024 |
| Mercury Properties Industrial Limited | Construction | 2015 |
| Mercy-N Hope Healthcare Limited | Health & social care | 2022 |
| Meres Limited | Transport & logistics | 2014 |
| Mergestatus Limited | Administrative & support | 1990 |
| Meridian Enterprises Europe Ltd. | Administrative & support | 2004 |
| Meridian Healthcare Partners Ltd | Extraterritorial | 2026 |
| Merit Creative Ltd | Professional & scientific | 2012 |
| Meritum Finance Services Limited | Professional & scientific | 2025 |
| Merivon Evermont Limited | Extraterritorial | 2026 |
| Merlin 2 DPC Ltd | Administrative & support | 2016 |
| Merlin Excavations Limited | Construction | 2003 |
| Merlot Training & Assessment Ltd | Education | 2021 |
| Merrion Properties Limited | Construction | 2019 |
| Merry Bough Music Limited | Information & communication | 2023 |
| Merry Mower Services Limited | Wholesale & retail | 2015 |
| Merto 97 Ltd | Hospitality | 2026 |
| Merv Mckenna Ltd | Transport & logistics | 2012 |
| Mesc Courrier & Cleaning Services Limited | Health & social care | 2014 |