| M & C Retail Limited | Wholesale & retail | 2016 |
| M & D Tyres Limited | Wholesale & retail | 2011 |
| M & E Consulting (North) Ltd | Professional & scientific | 2015 |
| M & E Investments (Leeds) Ltd | Real estate | 2019 |
| M & G Properties (Leeds) Ltd | Real estate | 2022 |
| M & J Auto Repair (Leeds) Limited | Wholesale & retail | 2011 |
| M & J Bagshaw Ltd | Hospitality | 2001 |
| M & K Autos Leeds Limited | Wholesale & retail | 2015 |
| M & K Investments Limited | Real estate | 2005 |
| M & L Couriers Leeds Ltd | Administrative & support | 2013 |
| M & LG Consulting Ltd | Professional & scientific | 2023 |
| M & M Blinds & Curtains Ltd | Wholesale & retail | 2015 |
| M & M Meat and Poultry Limited | Wholesale & retail | 2019 |
| M & M Print and Mail Limited | Manufacturing | 2019 |
| M & N Commodities Limited | Wholesale & retail | 2013 |
| M & N'S Playhouse Ltd | Arts & recreation | 2025 |
| M & P Joinery Limited | Construction | 2023 |
| M & P SON Ltd | Wholesale & retail | 2021 |
| M & S Cars Limited | Administrative & support | 2019 |
| M & S Oral Healthcare Limited | Health & social care | 2017 |
| M & S Properties (Leeds) Ltd | Real estate | 2017 |
| M & S Townend Ltd | Transport & logistics | 2021 |
| M & S Tyres Services Limited | Wholesale & retail | 2001 |
| M & T FOX Property LLP | | 2021 |
| M & Y Beauty Ltd | Other services | 2013 |
| M & Z Enterprises Limited | Information & communication | 1990 |
| M & Z Investments Group Limited | Wholesale & retail | 2025 |
| M & Z Trading Group Ltd | Wholesale & retail | 2025 |
| M a Grainge Property Services Ltd | Construction | 2026 |
| M a Miah Ltd | Professional & scientific | 2015 |
| M a Motors (Leeds) Limited | Wholesale & retail | 2013 |
| M a Properties 21 Limited | Real estate | 2025 |
| M a Watson Limited | Administrative & support | 2013 |
| M Ahmad Limited | Administrative & support | 2025 |
| M Ahmad Partnership LLP | | 2025 |
| M Ali's Driving School Ltd | Education | 2023 |
| M and EA Building Services Limited | Construction | 2013 |
| M and M Roofing Services and Building Ltd | Construction | 2025 |
| M Ashraf Ltd | Transport & logistics | 2026 |
| M B Models Limited | Manufacturing | 2014 |
| M Benson Plumbing & Heating Ltd | Construction | 2025 |
| M Biddles Ltd | Administrative & support | 2015 |
| M Bigglesworth Ltd | Administrative & support | 2024 |
| M Bilton Plumbing & Heating Ltd | Construction | 2026 |
| M C Doherty Ltd | Professional & scientific | 2022 |
| M Canavan Consulting Ltd | Health & social care | 2020 |
| M Carr Consultancy Services Limited | Administrative & support | 2019 |
| M D Simple Designs Limited | Wholesale & retail | 2017 |
| M E Willey Ltd | Professional & scientific | 2010 |
| M F G Interiors Ltd | Manufacturing | 2021 |
| M F J Mechanical Ltd | Construction | 2021 |
| M G Builders (UK) Limited | Construction | 2007 |
| M G Optics Ltd | Health & social care | 2014 |
| M G Plumbing & Maintenance Limited | Construction | 2003 |
| M H Mortgages Limited | Financial services | 2005 |
| M H Rail Track Services Ltd | Construction | 2018 |
| M H Yaqub Ltd | Wholesale & retail | 2002 |
| M Heggie Golf Centre Limited | Arts & recreation | 2013 |
| M J Automatic Gates Limited | Other services | 2017 |
| M J Business Consultancy Ltd | Information & communication | 2013 |
| M J Conneely (Groundworks) Limited | Construction | 2007 |
| M J Dennison Builders Limited | Construction | 2015 |
| M J Europe Limited | Wholesale & retail | 2012 |
| M J Nelson Plumbing & Heating Ltd | Construction | 2019 |
| M J Petfoods & Proteins Limited | Wholesale & retail | 2000 |
| M J Sillah Couriers Limited | Transport & logistics | 2025 |
| M K a C Property Investment Limited | Real estate | 2026 |
| M K Property Bramley Limited | Real estate | 2016 |
| M K R R Limited | Wholesale & retail | 2026 |
| M Kettlewell Properties Ltd | Households | 2021 |
| M Leeds Limited | Hospitality | 2026 |
| M Manir Ltd | Health & social care | 2023 |
| M Massey Limited | Financial services | 2021 |
| M N W Bakery Ltd | Manufacturing | 2014 |
| M Nazim Trader Ltd | Wholesale & retail | 2025 |
| M Northfield Limited | Transport & logistics | 2017 |
| M O M Transport Services Ltd | Transport & logistics | 2025 |
| M P Alarms (Fire and Security) Limited | Administrative & support | 2003 |
| M P Harrison Ltd | Construction | 2020 |
| M P Joinery & Building Ltd | Construction | 2026 |
| M Property Lettings & Management Ltd | Real estate | 2022 |
| M R a Financials Ltd | Other services | 2018 |
| M Realisations 2026 Limited | Manufacturing | 1972 |
| M Rodgerson Roofing Ltd | Construction | 2019 |
| M S B (Yorkshire) Limited | Other services | 2017 |
| M S Haulage (Yorkshire) Limited | Transport & logistics | 2017 |
| M S Medics Ltd | Health & social care | 2019 |
| M S&C Community Union | Administrative & support | 2025 |
| M Stelmach Ltd | Information & communication | 2019 |
| M T Deliveries Limited | Transport & logistics | 2025 |
| M T Electrical Services Limited | Construction | 2016 |
| M T Massage Ltd | Health & social care | 2023 |
| M Thackray Transport Ltd | Transport & logistics | 2025 |
| M Verity Plastering Ltd | Construction | 2023 |
| M W Partners Consulting Ltd | Information & communication | 2018 |
| M W Partners Ltd | Information & communication | 2015 |
| M Wood Barbering Ltd | Other services | 2021 |
| M Y Fazal Properties Ltd | Real estate | 2016 |
| M&A 21 Limited | Transport & logistics | 2025 |
| M&A Healthcare and Recruitment Ltd | Administrative & support | 2025 |