| Maximas (Services) Limited | Construction | 2014 |
| Maximise AI Ltd | Information & communication | 2024 |
| Maximise Learning Limited | Professional & scientific | 2025 |
| Maximum Brickwork Ltd | Construction | 2021 |
| Maximum Impact Services Ltd | Health & social care | 2018 |
| Maximum Speed Limited | Administrative & support | 2007 |
| Maximus Service Work Ltd | Professional & scientific | 2016 |
| Maxit Inc. Ltd | Wholesale & retail | 2015 |
| Maxkote Limited | Wholesale & retail | 2019 |
| Maxlogic Group Limited | Information & communication | 2021 |
| Maxlogic Holdings Limited | Information & communication | 2022 |
| Maxlogic LLP | | 2020 |
| Maxmilly Ltd | Arts & recreation | 2026 |
| Maxmore Ltd. | Transport & logistics | 2016 |
| Maxstays Ltd | Real estate | 2025 |
| Maxstorm Limited | Households | 2022 |
| Maxton Design Ltd | Wholesale & retail | 2014 |
| Maxton Design UK Holdings Ltd | Financial services | 2021 |
| Maxwell Office Ltd | Professional & scientific | 2024 |
| Maxwell Power Services Limited | Construction | 2022 |
| Maxwell Resources Ltd | Real estate | 2022 |
| MAY West Property Ltd | Real estate | 2019 |
| Maya & ALI Ltd | Hospitality | 2023 |
| Maya Admin Ltd | Public administration | 2026 |
| Maya Cleaning Services Ltd | Administrative & support | 2020 |
| Maya Concrete Services Ltd | Construction | 2024 |
| Maya Imaging Services Limited | Health & social care | 2018 |
| Maya Properties 3 Limited | Real estate | 2020 |
| Maya Transport Limited | Construction | 2013 |
| Mayaisha Holdings Ltd | Financial services | 2018 |
| Maybart Limited | Construction | 2021 |
| Maybe Baby Tsiempo Ltd | Hospitality | 2026 |
| Maybe Sailing Youth Initiative | Education | 2015 |
| Maycol Property Ltd | Real estate | 2023 |
| Mayday Yorkshire Limited | Professional & scientific | 2025 |
| Mayel Property Ltd | Financial services | 2026 |
| Mayfair Bites Limited | Hospitality | 2021 |
| Mayfair Commerce Ltd | Wholesale & retail | 2022 |
| Mayfair Curzon Properties Limited | Real estate | 2011 |
| Mayfair Estates (Leeds) Ltd | Real estate | 2015 |
| Mayfair Group Investment Ltd | Real estate | 2005 |
| Mayfair Investments in Yield Ltd | Real estate | 2018 |
| Mayfield Court (Horsforth) Limited | Real estate | 1993 |
| Mayfield Information Solutions Limited | Information & communication | 2010 |
| Mayfly Group Ltd | Construction | 2018 |
| Mayfly Hydronics Ltd | Construction | 2020 |
| Mayleen Ltd | Wholesale & retail | 2025 |
| Maymask (239) Limited | Real estate | 2020 |
| Maymask (245) Limited | Real estate | 2022 |
| Mayne Allstars Ltd | Arts & recreation | 2018 |
| Mayonnaise Treasure Limited | Wholesale & retail | 2023 |
| Mayonnaise Workshop Ltd | Education | 2025 |
| Maypole Education Services Ltd | Education | 2023 |
| Maypole Energy Limited | | 2012 |
| Maypole Frozen Foods Limited | Wholesale & retail | 2003 |
| Maypole Technology Limited | Professional & scientific | 2015 |
| Mayport Limited | Other services | 2018 |
| Mayrose Care and Support Ltd. | Health & social care | 2023 |
| Maysen Consulting Group Ltd | Professional & scientific | 2026 |
| Maysum Authentic Recipes Limited | Hospitality | 2015 |
| MAZ (Leeds) Limited | Real estate | 2015 |
| MAZ Hosiery UK Ltd | Wholesale & retail | 2013 |
| Maza Properties Ltd | Real estate | 2025 |
| Maza Restaurant Ltd | Hospitality | 2024 |
| Mazaad Limited | Real estate | 2025 |
| Mazapay Ltd | Administrative & support | 2023 |
| Mazar Function Room Ltd | Arts & recreation | 2025 |
| Mazar Welding & Gate Automations Ltd | Manufacturing | 2024 |
| Mazebrook Investments Limited | Real estate | 1982 |
| Mazel Assets Limited | Real estate | 2004 |
| Mazhar & Co (UK) Limited | Wholesale & retail | 2010 |
| Mazmabf Ltd | Wholesale & retail | 2020 |
| Mazza Chicken Burger Ltd | Hospitality | 2025 |
| Mazza Physiotherapy Ltd | Education | 2020 |
| MB (Yorks) Limited | Construction | 2019 |
| MB Care Group Limited | Health & social care | 2025 |
| MB Creative Artwork Limited | Professional & scientific | 2021 |
| MB Creative CAD Limited | Construction | 2024 |
| MB Decor (Yorkshire) Limited | Construction | 2014 |
| MB Design & Production Ltd | Construction | 2021 |
| MB Direct Ltd | Administrative & support | 2023 |
| MB Ducting Limited | Energy | 2021 |
| MB Estate 8888 Ltd | Real estate | 2021 |
| MB Foods (UK) Ltd | Wholesale & retail | 2010 |
| MB Handels GmbH Ltd | Hospitality | 2024 |
| MB Law Holdings Limited | Financial services | 2020 |
| MB Law Trustees Limited | Professional & scientific | 2026 |
| MB Leeds Construction Ltd | Construction | 2025 |
| MB Locums Ltd | Health & social care | 2022 |
| MB Plastering (Morley) Ltd | Construction | 2025 |
| MB Portfolio Management Ltd | Real estate | 2025 |
| MB Project Support Limited | Professional & scientific | 2010 |
| MB Property Investor Ltd | Real estate | 2017 |
| MB Real Estate Solutions Ltd | Real estate | 2025 |
| MB Solicitors Limited | Professional & scientific | 2008 |
| MB01 Holdings | Financial services | 2025 |
| MB1ST Solutions Limited | Professional & scientific | 2015 |
| MBA Recycling Ltd | Water & waste | 2021 |
| MBC Cover Limited | Financial services | 2011 |
| MBC Painting and Decorating Ltd | Construction | 2022 |