| Modanchi Limited | Wholesale & retail | 2015 |
| Modaunisexsalon Limited | Other services | 2023 |
| Modern Management Limited | Professional & scientific | 2014 |
| Modular Rocks Ltd | Information & communication | 2021 |
| Moksha & Co UK Ltd | Hospitality | 2025 |
| Momentsimages Ltd | Professional & scientific | 2012 |
| Momentum Elevators Ltd | Manufacturing | 2026 |
| Mondo Conservation Ltd | Agriculture & fishing | 2021 |
| Monocled Productions Limited | Arts & recreation | 2015 |
| Montyeno Ltd | Wholesale & retail | 2021 |
| Moonchild Pictures Ltd | Information & communication | 2022 |
| Moonrekha Limited | Professional & scientific | 2013 |
| Moore Acquisitions Ltd | Professional & scientific | 2023 |
| Moov.Me.Uk Limited | Information & communication | 2011 |
| Morgan Security Ltd | Administrative & support | 2025 |
| Morris Rigging Services Limited | Construction | 2021 |
| Morten & Sons Limited | Construction | 2012 |
| Morten & Sons of Warfield Limited | Construction | 2004 |
| Mortgage & Protection Solutions Limited | Financial services | 2013 |
| Mothercloud Ltd | Information & communication | 2017 |
| Mount Avalon Limited | Real estate | 2012 |
| Mount Olive Wellbeing Training Limited | Education | 2026 |
| Movetech Limited | Administrative & support | 2001 |
| Moving Matters Associates Limited | Transport & logistics | 2023 |
| Mowers and More Ltd | Manufacturing | 2013 |
| MP Investments Ltd | Real estate | 2023 |
| MP Pro Tiling Ltd | Construction | 2022 |
| MPH Electric Services Ltd | Construction | 2019 |
| Mpho Nail'D IT Ltd | Other services | 2026 |
| MPN Consultants Ltd | Professional & scientific | 2023 |
| MRM Executive Voyage Ltd | Transport & logistics | 2025 |
| MS Drylining Ltd | Construction | 2023 |
| MS Plumbing,Heating & Drainage Ltd | Construction | 2025 |
| MS Services Design Limited | Construction | 2015 |
| MSP Pro Clean Ltd | Administrative & support | 2022 |
| MTC Alloys & Metals Ltd | Wholesale & retail | 2025 |
| MTI Consultants LLP | | 2014 |
| MTP Foods Ltd | Wholesale & retail | 2026 |
| MTW Engineering Service Limited | Administrative & support | 2012 |
| Mulholland Electrical Limited | Construction | 2015 |
| Mulligan Club Limited | Arts & recreation | 2026 |
| Multi Modal Clearance Limited | Administrative & support | 2006 |
| Multicast Consultancy Limited | Professional & scientific | 2015 |
| Multimedia Developments Ltd. | Manufacturing | 1994 |
| Multipro Limited | Wholesale & retail | 1991 |
| Mumbojumbo Games Limited | Information & communication | 2007 |
| Mummsy Ltd | Professional & scientific | 2023 |
| Munamato Ltd | Health & social care | 2014 |
| Munsterhomes Ltd | Real estate | 2021 |
| Munyag Ltd | Health & social care | 2015 |
| Murphy Power Engineering Ltd | Professional & scientific | 2018 |
| Murray Care Ltd | Health & social care | 2015 |
| Muse and Music Ltd | Education | 2024 |
| Music ETC. Limited | Information & communication | 2023 |
| Musica Events Limited | Information & communication | 2022 |
| Musical Tree Limited | Education | 2002 |
| MV Bespoke Ltd | Manufacturing | 2025 |
| MVF Group Limited | Real estate | 1989 |
| MVP Elite Football Academy Ltd | Arts & recreation | 2025 |
| MWE Services and Installations Ltd | Other services | 2021 |
| Mxellence Ltd | Wholesale & retail | 2023 |
| MXM Technology Ltd | Manufacturing | 2023 |
| My Alter EGO Limited | Wholesale & retail | 2024 |
| My Dream Home Limited | Construction | 2022 |
| My Drone Pro Ltd | Information & communication | 2018 |
| My Eco Genie Ltd | Wholesale & retail | 2022 |
| My Lady Limited | Extraterritorial | 2025 |
| My Merchandise Limited | Wholesale & retail | 2020 |
| My Recycling Ltd | Water & waste | 2015 |
| My Resettlement Ltd | Information & communication | 2024 |
| Mycovoco Ltd | Professional & scientific | 2024 |
| Mygreatness UK Ltd | Health & social care | 2024 |
| Mync UK Limited | Real estate | 2017 |
| Myona Roofing Ltd | Construction | 2006 |
| Mypa Virtual Services LLP | | 2010 |
| Mystical Stones Limited | Wholesale & retail | 2021 |
| Mythic Cards Ltd | Wholesale & retail | 2024 |
| MZ Completion and Finishing Ltd | Construction | 2025 |
| Mziba Ltd | Health & social care | 2018 |
| N & L Cars Ltd | Wholesale & retail | 2022 |
| N a Residential Ltd | Real estate | 2026 |
| N G Analytics Limited | Administrative & support | 2016 |
| N G Sportswear International Limited | Administrative & support | 2010 |
| N M Inc LLP | | 2012 |
| N.C VA Solutions Ltd | Households | 2025 |
| Nacho's Polo Limited | Arts & recreation | 2008 |
| Nagoma Equity Investment Limited | Financial services | 2020 |
| Nail Talk Limited | Other services | 2003 |
| Nailora UK Limited | Wholesale & retail | 2025 |
| Nams Consultancy Limited | Information & communication | 2007 |
| Nams Investment Limited | Financial services | 2024 |
| Namsathy Consultancy Ltd | Information & communication | 2023 |
| Nanny Tango Ltd | Arts & recreation | 2018 |
| Nanodsl Properties Limited | Real estate | 2020 |
| Nanotech Coatings UK Limited | Wholesale & retail | 2013 |
| Nascon Ltd | Information & communication | 2026 |
| Nashdom Wilding Limited | Real estate | 2016 |
| National Freight Consortium Limited | Professional & scientific | 1987 |
| National PAT Testing Ltd | Extraterritorial | 2026 |
| Natural Resource Management Limited | Professional & scientific | 1991 |