| Macmillan Cooper Limited | Wholesale & retail | 2003 |
| Madeley Optical Ltd | Health & social care | 2015 |
| Magenta Prime Limited | Financial services | 2017 |
| Magical NAILS83 Ltd | Other services | 2026 |
| Magnum Steels Limited | | 1982 |
| Mainmill Property Management Limited | Households | 1982 |
| Mainwell Properties Ltd | Real estate | 2000 |
| Majik Properties Limited | Real estate | 1996 |
| Make Room Limited | Wholesale & retail | 2007 |
| Manchester Chinese Centre | Education | 2005 |
| Manchester Safety Services Limited | Wholesale & retail | 1979 |
| Mandarin Orange Limited | Wholesale & retail | 2005 |
| Mangham Electrical Services Limited | Construction | 2008 |
| Manhattan Joinery Limited | Construction | 2005 |
| Mann + Hummel Vokes Air Filtration Limited | Professional & scientific | 2003 |
| Mann + Hummel Vokes Air Treatment Holdings Limited | Professional & scientific | 1919 |
| Mann + Hummel Vokes-Air Limited | Manufacturing | 1978 |
| Mann + Hummel Wheway Limited | Professional & scientific | 1959 |
| Manor Apartments (LPG) Limited | Households | 2003 |
| Manor Homes (Poulton) Limited | Health & social care | 1982 |
| Mapleleaf Letting Centre Limited | Real estate | 2008 |
| Marc's Garage Limited | Wholesale & retail | 2004 |
| Marcherry Limited | Construction | 1995 |
| Marco Axis Limited | Professional & scientific | 2024 |
| Marcold Limited | Manufacturing | 2000 |
| Marfast & Co. Limited | Wholesale & retail | 1993 |
| Marie Crawford Beauty Therapy Ltd | Other services | 2003 |
| Marine Container Test Services Limited | Administrative & support | 2005 |
| Mark a Jones Limited | Construction | 2006 |
| Mark Cottam Limited | Construction | 2002 |
| Mark Iddon Ltd | Transport & logistics | 2007 |
| Mark Rigby Gardening Services Limited | Other services | 2003 |
| Mark Slater Electrical Limited | Construction | 2001 |
| Mark Storer Limited | Construction | 2002 |
| Mark-Up Tools Limited | Wholesale & retail | 1998 |
| Marland Electrical Engineering Co. Limited | Construction | 1961 |
| Marldon Gross Ltd | Wholesale & retail | 2025 |
| Marmion Gardner Ltd | Wholesale & retail | 2025 |
| Marnic Groundwork Limited | Construction | 1999 |
| Marsden Grange Residential Home for the Elderly | | 2002 |
| Marshlight Limited | Wholesale & retail | 2026 |
| Martian Arts Ltd. | Professional & scientific | 2001 |
| Martin Hughes Building Services Ltd | Wholesale & retail | 1998 |
| Martin Kasabov Ltd | Wholesale & retail | 2024 |
| Martyn Clegg Painting & Decorating Limited | Construction | 2002 |
| Marway Limited | Other services | 1996 |
| Mary Monson Solicitors Limited | Professional & scientific | 2007 |
| Mason Developments Lancashire Limited | Extraterritorial | 2007 |
| Masonic Assembly Rooms (Padiham) Limited | Other services | 1921 |
| Massey Forging Limited | Manufacturing | 2005 |
| Masters Holding Ltd | Real estate | 2020 |
| Matchspeed Limited | Real estate | 2003 |
| Matthew Marsden Furniture Limited | Manufacturing | 2005 |
| Matthew Whalley Light Haulage Limited | Transport & logistics | 2007 |
| Mawby Properties Limited | Real estate | 1999 |
| MAX Enterprises Ltd | Other services | 2002 |
| Mayble Limited | Hospitality | 2002 |
| Mayfair Residential Home Limited | Other services | 1998 |
| MC3 Solutions Limited | Information & communication | 2003 |
| MCB Print Limited | Manufacturing | 2002 |
| Mccreedy Inns Limited | Professional & scientific | 2001 |
| Mccreedy Restaurants Limited | Hospitality | 2001 |
| Mccrory Lease Ltd | Administrative & support | 2026 |
| Mcdade Roberts Accountants Limited | Professional & scientific | 1998 |
| Mcgarrie Transport Limited | Transport & logistics | 1995 |
| Mcleod Agencies Limited | Wholesale & retail | 2006 |
| Mcmurray Brothers Limited | Other services | 2003 |
| Mcshannon Trailer Sales Limited | Administrative & support | 2002 |
| MDS Group (NW) Ltd | Financial services | 2026 |
| Meat Direct Limited | Wholesale & retail | 2004 |
| Mechanical Engineering Services (UK) Limited | Professional & scientific | 2005 |
| Mechanical Technology Limited | Manufacturing | 1999 |
| Medimedia Limited | Other services | 2006 |
| Medlock Interiors (Leisure) Limited | Construction | 2002 |
| Meenawala Charitable Foundation Limited | Other services | 2007 |
| MEL Jones Photography Limited | Administrative & support | 2003 |
| Mellors & Makin Limited | Manufacturing | 2006 |
| Melville Norman Ltd | Wholesale & retail | 2025 |
| Memee Ltd | Information & communication | 2020 |
| Menai Mounts Ltd | Wholesale & retail | 2025 |
| Mereidea Limited | Information & communication | 2002 |
| Meridian G5M Ltd | Information & communication | 2019 |
| Metamark Group Holdings Limited | Financial services | 2017 |
| Metaphor Design & Advertising Ltd | Professional & scientific | 2005 |
| Metric Technique Limited | | 1991 |
| MGS Ltd | Construction | 2004 |
| MHC Property Services Limited | Administrative & support | 2006 |
| MHL Properties (UK) Limited | Real estate | 1999 |
| MHZ Delivery Ltd | Transport & logistics | 2025 |
| Michael Lomax Limited | Agriculture & fishing | 2002 |
| Michelle.B Limited | Wholesale & retail | 2004 |
| Microstage Limited | Information & communication | 1998 |
| Microtech Consultants Limited | Education | 1994 |
| Microtech Stationers Limited | Wholesale & retail | 2005 |
| Microview Data Systems Limited | Information & communication | 1997 |
| Midas Investments Limited | Real estate | 1993 |
| Midas Technologies Limited | Professional & scientific | 2007 |
| Middleton MOT Centre Limited | Wholesale & retail | 2005 |
| Mideas Limited | Professional & scientific | 2005 |
| Midgleys | | 2003 |