| Mediocre Productions Limited | Arts & recreation | 2012 |
| Meditrina Design Limited | Professional & scientific | 2018 |
| Megabiotics Health Products Limited | Wholesale & retail | 2020 |
| MEL TAN LAB Ltd | Other services | 2019 |
| Melcey Ltd | Wholesale & retail | 2026 |
| Melcom Systems Ltd | Administrative & support | 2019 |
| Melton & District Indoor Bowls Club Limited | Arts & recreation | 1987 |
| Melton & Oakham Waterways Society | Arts & recreation | 1999 |
| Melton Accident Repair Centre Limited | Wholesale & retail | 2020 |
| Melton and District Furniture Project | Other services | 2000 |
| Melton Barbers Ltd | Other services | 2022 |
| Melton Best Grill Ltd | Hospitality | 2026 |
| Melton Car Sales Limited | Real estate | 1996 |
| Melton Car Wash Ltd | Administrative & support | 2024 |
| Melton Care Services Limited | Other services | 2012 |
| Melton Chicken Ltd | Hospitality | 2026 |
| Melton Computers Limited | Wholesale & retail | 2015 |
| Melton Cycles CIC | Manufacturing | 2025 |
| Melton Design Limited | Professional & scientific | 2016 |
| Melton Emes Ltd | Construction | 2021 |
| Melton Festivals Ltd | Administrative & support | 2018 |
| Melton Fibre Glass Limited | Manufacturing | 1971 |
| Melton Flashings Limited | Construction | 1988 |
| Melton Foods Limited | Extraterritorial | 1996 |
| Melton Foot Clinic Limited | Public administration | 2016 |
| Melton Glass Limited | Construction | 1997 |
| Melton Hardware Limited | Wholesale & retail | 1997 |
| Melton Haulage Ltd | Transport & logistics | 2014 |
| Melton Learning Hub | Education | 2010 |
| Melton Meat Limited | Wholesale & retail | 1998 |
| Melton Memorials Ltd | Construction | 2017 |
| Melton Mencap | Health & social care | 2014 |
| Melton Messenger Ltd | Professional & scientific | 2008 |
| Melton Mowbray BID Company Limited | Administrative & support | 2011 |
| Melton Mowbray Business Park Ltd | Administrative & support | 2022 |
| Melton Mowbray Chamber of Trade(The) | Other services | 1984 |
| Melton Mowbray Food Partnership Limited | Hospitality | 2007 |
| Melton Mowbray Golf Club | Arts & recreation | 1990 |
| Melton Mowbray Pork Company Ltd | Agriculture & fishing | 2014 |
| Melton Mowbray RFC | Arts & recreation | 2018 |
| Melton Mowbray Tyre Recycling Limited | Water & waste | 2009 |
| Melton Pipework Installations Ltd | Construction | 2022 |
| Melton Plant Hire Ltd | Administrative & support | 2024 |
| Melton Plumbing Services Limited | Construction | 2014 |
| Melton Powered Access Limited | Administrative & support | 2023 |
| Melton Private Hire Limited | Transport & logistics | 2022 |
| Melton Space CIC | Manufacturing | 2019 |
| Melton Taxis Limited | Transport & logistics | 2021 |
| Melton Tech Limited | Other services | 2022 |
| Melton Tourer Services Ltd | Manufacturing | 2015 |
| Melton Town Football Club Ltd | Arts & recreation | 2020 |
| Melton Truck Ltd | Wholesale & retail | 2025 |
| Melton Vehicle Hire Limited | Administrative & support | 2020 |
| Melton Vineyard | Other services | 2012 |
| Melton Yarn Shop Limited | Wholesale & retail | 2026 |
| Melton's Welcome Cafe Ltd | Hospitality | 2022 |
| Melton, Rutland and the Vale Direct Cremations Ltd | Other services | 2025 |
| Meltonindoorgolf Ltd | Arts & recreation | 2026 |
| Melvale Property Limited | Real estate | 2023 |
| Menorca Property Holding Limited | Households | 2025 |
| Mercian Dynamics Limited | Financial services | 2018 |
| Meridian Innovation Ltd | Professional & scientific | 2020 |
| Metaphor Development Limited | Professional & scientific | 2008 |
| Methair Ltd | Other services | 2012 |
| Metro Educators Ltd | Education | 2014 |
| Metspec Limited | Administrative & support | 1998 |
| Mexichem Materials Ltd | Financial services | 2018 |
| Mexichem Specialty Compounds Limited | Manufacturing | 1981 |
| MEZ Partnership Limited | Real estate | 2026 |
| MH Trans Limited | Transport & logistics | 2017 |
| Michael Brown Composites Ltd | Manufacturing | 2017 |
| Mick Kettle Ltd | Other services | 2015 |
| Microban (Europe) Ltd. | Manufacturing | 1997 |
| Middy Services Ltd | Real estate | 2020 |
| Midland Ceilings Ltd | Construction | 2021 |
| Midland Lighting & Interiors Limited | Wholesale & retail | 2023 |
| Midland Markets & Events Limited | Administrative & support | 2014 |
| Midland Organ, Hele & Company Ltd | Administrative & support | 2007 |
| Midland Serviced Accommodation Limited | Real estate | 2019 |
| Midland Tail Lift Limited | Manufacturing | 2010 |
| Midland Truck Breakers Ltd | Water & waste | 2010 |
| Midlands Code LAB Ltd | Information & communication | 2026 |
| Midlands Marine Projects Limited | Administrative & support | 2002 |
| Midlands Property Lets Ltd | Real estate | 2024 |
| Midway Demolition and Groundworks Limited | Construction | 2002 |
| Mike Ford Estate Agents & Valuers Ltd | Real estate | 2017 |
| Miles Nurseries Ltd | Agriculture & fishing | 2003 |
| Mill Hill Limited | Construction | 2019 |
| Mill View (Long Clawson) Management Company Limited | Households | 2020 |
| Millhousedrummond Ltd | Construction | 2015 |
| Millie's Meats Ltd | Wholesale & retail | 2021 |
| Millions Impressions. Wall Print Ltd | Wholesale & retail | 2024 |
| Millstone Land & Property Limited | Financial services | 2026 |
| Millstream Cottages Limited | Households | 2003 |
| MILLY252 Properties Ltd | Real estate | 2024 |
| Milne Investments | Professional & scientific | 2018 |
| Milo Lifestyle Ltd | Wholesale & retail | 2022 |
| Milverton Hall RTM Company Limited | Households | 2025 |
| Mind GAP Business Consultancy Limited | Professional & scientific | 2013 |
| Mindful Animal Ltd | Education | 2018 |