| MH Temporary Works Limited | Construction | 2023 |
| MH Trading Group Ltd | Wholesale & retail | 2026 |
| Mhestablishment Ltd | Wholesale & retail | 2026 |
| MHF Investigations Ltd | Professional & scientific | 2024 |
| MHM Consultancy Ltd | Professional & scientific | 2018 |
| MHM IT Services Ltd | Information & communication | 2019 |
| MHM Legal Limited | Professional & scientific | 2021 |
| MI HE Properties Ltd | Real estate | 2024 |
| MI Medicare Ltd | Health & social care | 2017 |
| MI Techz Ltd | Wholesale & retail | 2023 |
| MIB Properties Yorkshire Limited | Real estate | 2023 |
| Mibz Developments Limited | Real estate | 2004 |
| Micassa UK Ltd | Wholesale & retail | 2023 |
| Michael Nicholson Limited | Construction | 2002 |
| Microcourt Limited | Wholesale & retail | 2001 |
| Middleton Park Limited | Wholesale & retail | 2014 |
| Midland Halal Ltd | Wholesale & retail | 2003 |
| Midnight Comfort Ltd | Other services | 2019 |
| MIE Locum Ltd | Health & social care | 2018 |
| Mike Roebuck Consulting (UK) Limited | Professional & scientific | 2001 |
| Millpond Petroleum LLP | | 2011 |
| Millpond Service Station Ltd | Wholesale & retail | 2024 |
| Millys Chippy Ltd | Hospitality | 2026 |
| Minibeast Adventures Ltd | Education | 2021 |
| Minova Limited | Extraterritorial | 1990 |
| Minster Auto Body Shop Ltd | Wholesale & retail | 2024 |
| Mirzyris Ltd | Health & social care | 2022 |
| Mistohorizon Ltd | Information & communication | 2025 |
| Mitha Greenwood Ltd | Real estate | 2025 |
| Mito Pavan Ltd | Arts & recreation | 2022 |
| MIX Colours Trading Ltd | Wholesale & retail | 2018 |
| MJ Autotec Ltd | Wholesale & retail | 2024 |
| MJ Developments (Leeds) Ltd | Water & waste | 2015 |
| MJ Developments (Parsons House) Limited | Water & waste | 2020 |
| MJ Energy Services Ltd | Wholesale & retail | 2023 |
| MJF IT Limited | Information & communication | 2024 |
| MK Indemnification Limited | Financial services | 2019 |
| MK Nexus Enterprise Ltd | Wholesale & retail | 2025 |
| MK Upholstery Ltd | Manufacturing | 2022 |
| MKB Exclusive Limited | Other services | 2020 |
| MKM Locum Ltd | Health & social care | 2018 |
| MKS Investments Limited | Real estate | 2009 |
| Mkss Local Shop Limited | Wholesale & retail | 2025 |
| MM Visioncare Ltd | Health & social care | 2013 |
| MMB Online Ltd | Wholesale & retail | 2024 |
| MMB Optical Ltd | Health & social care | 2023 |
| MMZ Enterprises Limited | Professional & scientific | 2025 |
| MN Drive Ltd | Transport & logistics | 2026 |
| MN Investments(Uk) Ltd | Real estate | 2021 |
| MNA Distributors Ltd | Wholesale & retail | 2017 |
| MNB Traders Ltd | Wholesale & retail | 2025 |
| Mngwenya Limited | Health & social care | 2014 |
| MOB Autos Ltd | Wholesale & retail | 2019 |
| Moffootwear Ltd | Wholesale & retail | 2024 |
| Mohammad Rafiq Properties Limited | Real estate | 2017 |
| Mohammedfabrics Limited | Wholesale & retail | 2025 |
| Momentous IT Limited | Information & communication | 2024 |
| Money Matters (Yorkshire) Limited | Wholesale & retail | 2013 |
| Moneza Beds Ltd | Manufacturing | 2020 |
| Montano's Food Ltd | Hospitality | 2025 |
| Moorfield Motors Ltd | Wholesale & retail | 2024 |
| Moorside Electrical Ltd | Construction | 2020 |
| Moosa's Software Strategies Ltd | Information & communication | 2025 |
| Morale Holdings Ltd | Real estate | 2014 |
| Moreish Cuisine Ltd | Hospitality | 2020 |
| Mortgages Through Ammar Ltd | Financial services | 2020 |
| Mossaqo Ltd | Wholesale & retail | 2025 |
| Motion Tech Group Limited | Other services | 2025 |
| Motivated UK Ltd | Hospitality | 2025 |
| Motorlenz Ltd | Wholesale & retail | 2026 |
| Mototech (UK) Limited | Wholesale & retail | 2009 |
| Mount Filling Systems Ltd | Manufacturing | 2025 |
| Mount FS Holdings Ltd | Financial services | 2025 |
| Mount Machinery Spares and Support Ltd | Manufacturing | 2025 |
| Movelogic Logistics Ltd | Transport & logistics | 2026 |
| MOW & Glow Ltd | Administrative & support | 2025 |
| MP Sports & Education Specialists Ltd | Education | 2023 |
| Mpse Community Engagement C.I.C. | Education | 2023 |
| MQ Prestige Beds Ltd | Manufacturing | 2025 |
| MR Fatayer Limited | Hospitality | 2025 |
| MR Juicy Ice Creams Limited | Hospitality | 2026 |
| MRB Capital UK Limited | Other services | 2020 |
| Mrdistributor Ltd | Wholesale & retail | 2026 |
| Mrfelevenplustuition Ltd | Education | 2011 |
| MRN Properties Ltd | Other services | 2015 |
| MRP Accountants Limited | Professional & scientific | 2025 |
| MS DIY Ltd | Wholesale & retail | 2023 |
| MS Trading Service Limited | Transport & logistics | 2024 |
| Mshomeworld Ltd | Manufacturing | 2021 |
| Msinternationalrecruitment Ltd | Administrative & support | 2024 |
| Msma Property Holdings Ltd | Real estate | 2025 |
| MTF Global Ltd | Hospitality | 2020 |
| MTR Rental Properties Limited | Real estate | 2017 |
| MU Executives Limited | Health & social care | 2023 |
| Muhammad NOM Ltd | Wholesale & retail | 2025 |
| Muhammad Shoaib Hanif Qazi Ltd | Wholesale & retail | 2025 |
| Muhammad Sohail Riasat Delivery Ltd | Transport & logistics | 2026 |
| MUJ Electrical Ltd | Professional & scientific | 2020 |
| Mukhtar Traders Ltd | Wholesale & retail | 2025 |
| Mulla Investment Limited | Real estate | 2023 |