| Luca Performance Limited | Wholesale & retail | 2024 |
| Luffships (UK 2026) Limited | Professional & scientific | 2024 |
| Luffships Limited | Wholesale & retail | 2010 |
| Luminate Development Limited | Other services | 2010 |
| Lumm Limited | Arts & recreation | 2025 |
| Lutley Care Limited | Health & social care | 2008 |
| Luxe Adventures Ltd | Administrative & support | 2025 |
| Luxe Lakes Limited | Real estate | 2024 |
| Luxe Lash and Beauty Limited | Other services | 2019 |
| Luxe Photographic Experiences Ltd | Professional & scientific | 2024 |
| Luxe Training and Tanning Ltd | Other services | 2021 |
| Luxury Bathroom Installations Limited | Construction | 2016 |
| LVW Beauty Clinic Ltd | Other services | 2009 |
| LWS Project Services Limited | Professional & scientific | 2016 |
| Lyde Green Tyres Ltd | Wholesale & retail | 2021 |
| LYE Close Stables Ltd | Agriculture & fishing | 2021 |
| Lynch Robert's Property Services Ltd | Real estate | 2021 |
| Lyttleton Court Limited | Real estate | 2005 |
| Lyttleton Court Management Company Ltd | Real estate | 2025 |
| M & D Properties Limited | Real estate | 2015 |
| M & F Atkins Ltd | Extraterritorial | 2011 |
| M & L Homes Ltd | Real estate | 2011 |
| M & M Outdoor Media Ltd | Administrative & support | 2003 |
| M & S Metals Limited | Manufacturing | 2000 |
| M & T Stores & Properties Limited | Construction | 1985 |
| M Gennard General Builders Limited | Construction | 2011 |
| M H Property Investments Limited | Real estate | 2012 |
| M P Sports Cars Limited | Wholesale & retail | 2017 |
| M Shipley Limited | Extraterritorial | 2002 |
| M T Henrick Limited | Manufacturing | 1972 |
| M W Coleman Limited | Other services | 1991 |
| M Woolman Solutions Limited | Construction | 2016 |
| M&A Hub Limited | Wholesale & retail | 2025 |
| M&H 16 Limited | Hospitality | 2025 |
| M&L Homes Services Ltd | Real estate | 2025 |
| M&M Tailor and Alterations Ltd | Wholesale & retail | 2025 |
| M. & Co Plastering and External Wall Insulations Limited | Construction | 2013 |
| M. & G. Builders (Kidderminster) Limited | Construction | 1977 |
| M.D. Construction & Building Services Limited | Construction | 2006 |
| M2 Living Ltd | Real estate | 2017 |
| M2M Outbuilding Ltd. | Manufacturing | 2017 |
| M3 Trades Ltd | Construction | 2020 |
| Mabuhay Consulting Limited | Professional & scientific | 2018 |
| MAC Machining Limited | Other services | 1994 |
| Machinery Safety Compliance Services Limited | Administrative & support | 2012 |
| Machining Solutions Group Ltd | Wholesale & retail | 2025 |
| Machining Solutions Ltd | Wholesale & retail | 2011 |
| Macrotrade Limited | Other services | 2017 |
| Macs Draughting Limited | Professional & scientific | 2019 |
| Macs Solutions Ltd | Financial services | 2021 |
| Made in the Jewellery Quarter Ltd | Wholesale & retail | 2022 |
| Madison York Limited | Professional & scientific | 2020 |
| Magic Moments Online Ltd | Wholesale & retail | 2022 |
| Magnum Financial Ltd | Professional & scientific | 2024 |
| Magreal Industrial Estate (Ladywood) Management Company Limited | Professional & scientific | 1999 |
| MAH Contracting Services Limited | Construction | 2011 |
| Mahf Pharma Limited | Health & social care | 2025 |
| Mahoora Limited | Hospitality | 2021 |
| Maid From Heaven Ltd | Administrative & support | 2011 |
| Maid in Cradley Ltd | Administrative & support | 2021 |
| Maintain Weight Management Solutions Ltd | Health & social care | 2025 |
| Majj Limited | Administrative & support | 2013 |
| Make Smthn, Feel Smthn Ltd | Arts & recreation | 2025 |
| MAL Storey Angling Centre Ltd | Wholesale & retail | 2015 |
| Malvern Electrical Wholesale Limited | Wholesale & retail | 1984 |
| Malverns Classic Limited | Arts & recreation | 2017 |
| Manaverse Ltd | Information & communication | 2025 |
| Mander and Sons Ltd | Manufacturing | 2012 |
| Mander Haulage Ltd | Transport & logistics | 2020 |
| Mangos Preloved Ltd | Wholesale & retail | 2026 |
| Manifold Games Ltd | Information & communication | 2020 |
| Manmade Designs Ltd | Wholesale & retail | 2016 |
| Manmy Property Ltd | Real estate | 2025 |
| Manor Abbey Investments Company Limited | Construction | 1959 |
| Manor Abbey Limited | Professional & scientific | 2016 |
| Manor Abbey Surveyor Ltd | Professional & scientific | 2025 |
| Manor Classic Cars Limited | Wholesale & retail | 2015 |
| Manor Farm Stables Limited | Hospitality | 2002 |
| Manor Optical Co. Limited | Manufacturing | 1961 |
| Mansoor Hussain Ltd | Health & social care | 2025 |
| Manuli Hydraulics UK Limited | Mining & quarrying | 2002 |
| Manvir RAI Photographer Limited | Professional & scientific | 2018 |
| MAP Industrial Limited | Administrative & support | 2023 |
| Mapei (UK) Limited | Manufacturing | 1989 |
| Maple (432) Limited | Households | 2018 |
| Maple Court (West Bromwich) Management Limited | Construction | 1985 |
| Maple Leaf Haulage Limited | Transport & logistics | 2025 |
| Mariet Media Limited | Professional & scientific | 2019 |
| Marigold Construction Developments Ltd | Real estate | 2022 |
| Marigold Insulation UK Ltd | Construction | 2015 |
| Mariner Holdings Limited | Professional & scientific | 1995 |
| Mariposa Enterprises Ltd | Wholesale & retail | 2015 |
| Mariposa Property Limited | Real estate | 2020 |
| Mark Blakeway Limited | Administrative & support | 2015 |
| Mark Davies Film Editor Limited | Information & communication | 2004 |
| Mark Horgan Ltd | Transport & logistics | 2025 |
| MARK3D UK Limited | Manufacturing | 2017 |
| Market Smarter Ltd | Education | 2018 |
| Marlboro Windows Limited | | 1983 |
| Marnei Music Limited | Information & communication | 2018 |