| Metallix Holdings Ltd | Professional & scientific | 2025 |
| Metalsmith (Leeds) Limited | Wholesale & retail | 2015 |
| Metalwork Fabrications Limited | Manufacturing | 2013 |
| Metamax Solutions Limited | Professional & scientific | 2022 |
| Metamorphosis Films Limited | Information & communication | 2025 |
| Metaventures Limited | Administrative & support | 2015 |
| Metaverse Innovation Hub Ltd | Information & communication | 2025 |
| Metaverse Network Limited | Administrative & support | 2015 |
| Metcalf Autos Limited | Wholesale & retail | 2008 |
| Metcalfe Property Group Ltd | Real estate | 2021 |
| Metcalfe Property Limited | Real estate | 2021 |
| Metcalfe Software Ltd. | Information & communication | 1995 |
| Metcon Leeds Limited | Arts & recreation | 2019 |
| Meter Manager Limited | Wholesale & retail | 2001 |
| Meteronline Limited | Wholesale & retail | 2015 |
| Methane and Plumbing Ltd | Construction | 2023 |
| Methley (Main Street) Management Company Limited | Real estate | 2023 |
| Methley Court Management Limited | Households | 2002 |
| Methley United AFC CIC | Arts & recreation | 2023 |
| Methley Warriors Arlfc CIC | Arts & recreation | 2025 |
| Method Analytics Ltd | Information & communication | 2016 |
| Metice Development Solutions Limited | Professional & scientific | 2004 |
| Metis Bidco Limited | Professional & scientific | 2011 |
| Metis Care Limited | Health & social care | 2021 |
| Metis Law Chambers Ltd | Professional & scientific | 2024 |
| Metis Law Limited | Professional & scientific | 2017 |
| Metis Law Partners LLP | | 2009 |
| Metpak Group Limited | Manufacturing | 2014 |
| Metprint Limited | Manufacturing | 2014 |
| Metre Squared Ltd | Construction | 2026 |
| Metre Squared Tiling Limited | Construction | 2016 |
| Metric AI Limited | Information & communication | 2024 |
| Metrin Skincare Europe Limited | Wholesale & retail | 2004 |
| Metro Bazaar Foods Ltd | Wholesale & retail | 2025 |
| Metro Financial Services Ltd | Professional & scientific | 2014 |
| Metro Leeds Market Limited | Wholesale & retail | 2024 |
| Metrodent Limited | Wholesale & retail | 1936 |
| Metropolis Homes Ltd | Real estate | 2023 |
| Metropolitan Borough of Wirral Fund KCP1 L.P. | | 2007 |
| Metsuki Holding Limited | Hospitality | 2022 |
| Mevie Ltd | Administrative & support | 2011 |
| Mews (Oakhampton Court) Management Company Limited(The) | Households | 1987 |
| Mexicandy UK Ltd | Hospitality | 2021 |
| Mexicanwey Ltd | Hospitality | 2023 |
| Meyrick Property Ventures Ltd | Households | 2025 |
| MEZ Property Renovations Ltd | Construction | 2025 |
| Mezzo Studio Holdings Limited | Professional & scientific | 2015 |
| Me‘N’Yuh Ltd. | Information & communication | 2020 |
| MF Bricklayer Ltd | Construction | 2023 |
| MF Car & Commercial Repairs Ltd | Wholesale & retail | 2020 |
| MF Newburn Property Limited | Construction | 2024 |
| MF Properties (Leeds) Ltd | Real estate | 2025 |
| MF Property Holdings Ltd | Real estate | 1947 |
| MF Refurbishments Ltd | Construction | 2025 |
| MFA Consulting Services Ltd | Professional & scientific | 2023 |
| MFA Contractors Ltd | Real estate | 2014 |
| Mfasl Ltd | Financial services | 2014 |
| Mfav Ltd | Construction | 2019 |
| MFD Consulting Limited | Professional & scientific | 2018 |
| MFG Commercial Cleaning Services UK Limited | Administrative & support | 2024 |
| Mfit Ltd | Manufacturing | 2026 |
| MFJ Glass Ltd | Manufacturing | 2020 |
| MFL Healthcare Ltd | Manufacturing | 2019 |
| MFS Multi Structure Ltd | Professional & scientific | 2013 |
| MFS Parcel Delivery Ltd | Transport & logistics | 2019 |
| MFS Response Limited | Professional & scientific | 2020 |
| MFZ Consultancy Ltd | Professional & scientific | 2026 |
| MG & M Care Services Limited | Health & social care | 2016 |
| MG Business Solutions Ltd | Professional & scientific | 2003 |
| MG Car Sales (Leeds) Ltd | Other services | 2015 |
| MG Fleet Solutions Limited | Other services | 2008 |
| MG Global Ventures Ltd | Wholesale & retail | 2015 |
| MG Property Services and Development Ltd | Real estate | 2026 |
| MG Trimz Ltd | Other services | 2026 |
| MG Ventures Limited | Extraterritorial | 2010 |
| MG Welding Services Ltd | Manufacturing | 2021 |
| MG Wright Consulting Limited | Information & communication | 2018 |
| MG53 Limited | Financial services | 2021 |
| MGD Reality Ltd | Financial services | 2025 |
| Mgdc Properties Limited | Real estate | 2018 |
| MGH Aesthetica Ltd | Other services | 2025 |
| MGH Bespoke Medicals Limited | Administrative & support | 2019 |
| MGH Bespoke Properties Ltd | Real estate | 2019 |
| MGH Management Services Ltd | Information & communication | 2023 |
| MGI Management Services Limited | Administrative & support | 2019 |
| Mgjg and Associates Limited | Health & social care | 2021 |
| Mgmc Engineering Ltd | Administrative & support | 2017 |
| MGP Management Ltd | Information & communication | 2014 |
| Mgrace UK Ltd | Other services | 2024 |
| MGS Components Ltd | Wholesale & retail | 2024 |
| MGW Creative Ltd | Professional & scientific | 2022 |
| MGY Services Ltd | Real estate | 2023 |
| MH Bookkeeping & Business Services Ltd | Professional & scientific | 2024 |
| MH Consulting (Leeds) Ltd | Professional & scientific | 2018 |
| MH Elmamoun Ltd | Health & social care | 2018 |
| MH Forde Ltd | Hospitality | 2021 |
| MH Freight & Logistics Limited | Transport & logistics | 2026 |
| MH Group Middlesbrough Ltd | Hospitality | 2022 |
| MH Opticare Limited | Health & social care | 2021 |
| MH Property Group Ltd | Real estate | 2025 |