| Mahmood & Hussain Company Ltd | Health & social care | 2022 |
| Mahmud Pharma Limited | Health & social care | 2025 |
| Mahvi Properties Ltd | Real estate | 2024 |
| Mai's LIPS6 Beauty Bar Ltd | Other services | 2019 |
| Maibridge Limited | Financial services | 2017 |
| Maicymoo Limited | Professional & scientific | 2022 |
| Maid to Fit Limited | Wholesale & retail | 2017 |
| Maid YOU Look Ltd | Administrative & support | 2025 |
| MAID2AIDE Ltd | Administrative & support | 2023 |
| Maiden-Voyage.Com Limited | Information & communication | 2008 |
| Maids in Leeds Limited | Households | 2025 |
| Mail Box Express Limited | Transport & logistics | 1994 |
| Mailbox Internet Limited | Information & communication | 1995 |
| Mailbox Medical Limited | Transport & logistics | 2025 |
| Mailflow Solutions Limited | Other services | 2014 |
| Mailing & Marketing Solutions Ltd | Transport & logistics | 2014 |
| Maim & Co Ltd | Wholesale & retail | 2022 |
| Main Marketing Ltd | Administrative & support | 2019 |
| Maine Distribution UK Ltd | Wholesale & retail | 2016 |
| Mainestream Consulting Ltd | Information & communication | 2024 |
| Mainline Computers Limited | Information & communication | 2003 |
| Mainrim Limited | Financial services | 1989 |
| Mains Chlorination Ltd | Extraterritorial | 2010 |
| Mainstreet (Bingley) Ltd | Hospitality | 2019 |
| Maintain Property Services Ltd | Construction | 2016 |
| Maintenance & Property Services Limited | Construction | 2026 |
| Mairki Ltd | Manufacturing | 2023 |
| Mais Properties Ltd | Real estate | 2023 |
| Maison Amore Limited | Wholesale & retail | 1997 |
| Maison DU Contour Ltd | Other services | 2025 |
| Maison Giorgia Ltd | Wholesale & retail | 2025 |
| Maison Haven Ltd | Wholesale & retail | 2026 |
| Maison Kalay Ltd | Wholesale & retail | 2025 |
| Maison Mouettes Ltd | Real estate | 2021 |
| Maison Parer Ltd | Manufacturing | 2025 |
| Maison Parfaite Estates Ltd | Real estate | 2018 |
| Maison Parfaite HG1 Ltd | Hospitality | 2023 |
| Maison Parfaite Investments Ltd | Real estate | 2019 |
| Maison Parfaite LS1 LLP | | 2019 |
| Maison Parfaite Ltd | Real estate | 2018 |
| Maison Parfaite Nydsley Hall Ltd | Real estate | 2018 |
| Maison Sance Limited | Health & social care | 2023 |
| Maisons Homes Ltd | Real estate | 2019 |
| Maisy's Limited | Extraterritorial | 2010 |
| Maitana Portuguese Beauty Ltd | Other services | 2018 |
| Maitri Estates Limited | Real estate | 2025 |
| Maiz Eats Ltd | Manufacturing | 2023 |
| Maizecor Foods Limited | Manufacturing | 1991 |
| MAJ Building & Joinery Ltd | Construction | 2024 |
| MAJ Building Contractors Ltd | Construction | 2017 |
| MAJ Hi-Spec Limited | Manufacturing | 1946 |
| Maja Scaffolding Ltd | Construction | 2024 |
| Majajan Boutique Ltd | Wholesale & retail | 2024 |
| Majeed Solicitors Ltd | Professional & scientific | 2021 |
| Majestic Carpets and Floorings Limited | Wholesale & retail | 2026 |
| Majestic Cheveux Ltd | Manufacturing | 2021 |
| Majestic Cosmo Ltd. | Manufacturing | 2016 |
| Majestic Event Catering Limited | Hospitality | 2024 |
| Majestic Gardens UK Limited | Administrative & support | 2004 |
| Majestic Household Ltd | Wholesale & retail | 2025 |
| Majestic Property Portfolio Ltd | Real estate | 2022 |
| Majestique Trading Ltd | Transport & logistics | 2008 |
| Majid Takeaway Ltd | Hospitality | 2026 |
| Major League Sports Academy Ltd | Education | 2020 |
| Major Sheet Metals Limited | Manufacturing | 2012 |
| Major Signs Limited | Manufacturing | 2021 |
| Majura Films Ltd | Information & communication | 2019 |
| Majzob Mini Market Ltd | Wholesale & retail | 2026 |
| MAK Accounting Ltd. | Professional & scientific | 2018 |
| MAK Electronics Ltd | Wholesale & retail | 2025 |
| MAK Restaurant Ltd | Hospitality | 2019 |
| Maka's Healthcare Ltd | Health & social care | 2018 |
| Makaka Ltd. | Health & social care | 2014 |
| Makarios Hands Limited | Health & social care | 2025 |
| Make & DO Limited | Extraterritorial | 1989 |
| Make and Test Ltd | Professional & scientific | 2016 |
| Make Holdings Limited | Financial services | 2026 |
| Make IT Easy LAB Ltd | Professional & scientific | 2022 |
| Make IT Happen Agency Limited | Wholesale & retail | 2012 |
| Make IT Playful Limited | Extraterritorial | 2025 |
| Make Online Limited | Information & communication | 2007 |
| Make Work Matter Limited | Professional & scientific | 2023 |
| Make Your Copy Count Ltd | Professional & scientific | 2017 |
| Makeapayment Limited | Transport & logistics | 2024 |
| Makebetteryou Ltd | Education | 2026 |
| Maker's Own Ltd | Arts & recreation | 2017 |
| Makers of Diamond Jewellery Limited | Wholesale & retail | 2010 |
| Makesense Properties Limited | Real estate | 1975 |
| Makesure Cover Limited | Construction | 2025 |
| Makhlouf HR Consulting Ltd | Professional & scientific | 2015 |
| Maki Transport Ltd | Transport & logistics | 2012 |
| Makin Air Limited | Transport & logistics | 2016 |
| Makin Developments Wakefield Ltd | Agriculture & fishing | 2014 |
| Making Changes Counselling Practice Ltd | Health & social care | 2023 |
| Making Influence Real and Responsible CIC | Education | 2025 |
| Making Light Work Limited | Agriculture & fishing | 1997 |
| Makins Enterprises Ltd | Agriculture & fishing | 2021 |
| Makins Soft Fruit Ltd | Agriculture & fishing | 2014 |
| Makkah International Foods Ltd | Wholesale & retail | 2016 |
| Mako Apac Ltd | Administrative & support | 2022 |