| Morley Property Consulting Ltd | Professional & scientific | 2025 |
| Morotos Films Ltd | Information & communication | 2024 |
| Morpheus Environmental Consulting Ltd | Professional & scientific | 2016 |
| Morpheus Motorcycles Ltd | Wholesale & retail | 2011 |
| Morpheus RM Limited | Information & communication | 2004 |
| Morpheus Thermal Designs Ltd | Professional & scientific | 2021 |
| Morphism Technologies Limited | Information & communication | 2021 |
| Morpho Holdings Limited | Financial services | 2024 |
| Morrells Woodfinishes Limited | Manufacturing | 1995 |
| Morrigan Consulting Ltd | Professional & scientific | 2022 |
| Morrigan Dentistry Limited | Health & social care | 2022 |
| Morrigan Investments Limited | Real estate | 2022 |
| Morris Assets Limited | Real estate | 2022 |
| Morris Place Care Ltd | Health & social care | 2014 |
| Morris's Barber Shop Limited | Other services | 2025 |
| Morrish & Wilson Ltd | Construction | 2021 |
| Morriston Tech Gadgets Ltd | Other services | 2025 |
| Morrow Digital Ltd | Information & communication | 2018 |
| Morse Networks Ltd | Information & communication | 2004 |
| Mortar and Brick Ltd | Real estate | 2020 |
| Mortgage Advice Partners FS Ltd | Financial services | 2026 |
| Mortgage Connect Ltd. | Financial services | 2011 |
| Mortgage Indeed Ltd | Financial services | 2016 |
| Mortgage Style Ltd | Financial services | 2006 |
| Mortgages Explained Limited | Financial services | 2007 |
| Mortgages in Bristol Limited | Financial services | 2014 |
| Mortimer Investments Limited | Construction | 2002 |
| Mortimer Regent Ltd | Other services | 2013 |
| Mortimore Developments Limited | Construction | 2008 |
| Mortlake Properties Limited | Real estate | 1950 |
| Morton Commercial Cleaning Ltd | Administrative & support | 2022 |
| Morton Dime Limited | Professional & scientific | 2015 |
| Morton Dog House Limited | Other services | 2024 |
| Morton Leisure Limited | Wholesale & retail | 2023 |
| Morton Meadows (Thornbury) Management Company Limited | Households | 2020 |
| Morton Mill Management Limited | Real estate | 1992 |
| Morton Productions Ltd | Information & communication | 2019 |
| Morton Property Consultants Ltd | Real estate | 2017 |
| Morton Storm Limited | Professional & scientific | 2012 |
| Morton Technologies Ltd | Professional & scientific | 2016 |
| Morvan Foods Partnership | | 2001 |
| Morzine Enterprise Parks Ltd | Construction | 2022 |
| Morzine Group Limited | Financial services | 2019 |
| Morzine Sport Promotions Ltd | Professional & scientific | 2025 |
| MOS Accountancy Limited | Professional & scientific | 2023 |
| MOS Advisory Limited | Professional & scientific | 2023 |
| Mosa International Services Limited | Information & communication | 2021 |
| Mosah Limited | Wholesale & retail | 2019 |
| Mosaic Byte Ltd | Information & communication | 2015 |
| Mosaic Island Ltd | Information & communication | 2006 |
| Mosaic Madness Limited | Education | 2010 |
| Mosaic Management Publishing Limited | | 1980 |
| Mosaic Marketing Operations Ltd | Professional & scientific | 2023 |
| Mosaic Partnership Trust | Education | 2024 |
| Mosaic South West Limited | Extraterritorial | 2026 |
| Mose Social Rising C.I.C. | Health & social care | 2023 |
| Moseley Distributors Limited | Wholesale & retail | 1968 |
| Moss Bristol Limited | Construction | 2000 |
| Moss Enterprises Limited | Wholesale & retail | 2003 |
| Moss Home Improvements Ltd | Construction | 2021 |
| Moss Impex Ltd | Wholesale & retail | 2025 |
| Mossive Productions Limited | Information & communication | 2022 |
| Mossleen Ltd | Wholesale & retail | 2025 |
| Mossy Roofing Ltd | Construction | 2025 |
| Most Eco Friendly Limited | Administrative & support | 2022 |
| Most High Foods Ltd | Wholesale & retail | 2016 |
| Mostly Harmless Limited | Professional & scientific | 2001 |
| Mostly White Rabbit Limited | Information & communication | 2016 |
| Mostyn Lodge Keynsham Limited | Health & social care | 2004 |
| Mostyn Project Solutions Limited | Construction | 2021 |
| Mosunon Properties Limited | Real estate | 2024 |
| MOT Group Ltd | Wholesale & retail | 2024 |
| MOT Ltd | Wholesale & retail | 2004 |
| Mota Creative Ltd | Information & communication | 2018 |
| Motaman (Bristol) Limited | Real estate | 1985 |
| Motaparts Downend Limited | Wholesale & retail | 2014 |
| Motaparts Ltd | Wholesale & retail | 2025 |
| Motb Property Ltd | Real estate | 2021 |
| Motem Limited | Professional & scientific | 2016 |
| Mothers for Mothers | Health & social care | 2013 |
| Mothhart Limited | Real estate | 2024 |
| Motif Leisure Limited | | 2012 |
| Motion Automatics Ltd | Construction | 2025 |
| Motion Control Ltd | Manufacturing | 2006 |
| Motion Events Ltd | Hospitality | 2005 |
| Motion Fit Ltd | Other services | 2016 |
| Motion Impossible Ltd | Manufacturing | 2015 |
| Motion Printing Ltd | Manufacturing | 2014 |
| Motion Robots Ltd | Manufacturing | 2019 |
| Motion Services Ltd | Construction | 2024 |
| Motionsupply Ltd | Wholesale & retail | 2025 |
| Motiq 2 (Clifton Arcade) Ltd | Wholesale & retail | 2023 |
| Motiva Implants UK Limited | Wholesale & retail | 2018 |
| Motivation Assistive Technology CIC | Health & social care | 2026 |
| Motive Content Ltd | Administrative & support | 2014 |
| Motive Mobile App Ltd | Arts & recreation | 2023 |
| Motives International Limited | Information & communication | 2021 |
| Motmot Coffee Ltd | Hospitality | 2025 |
| Moto Elite Service Centre Limited | Wholesale & retail | 2016 |
| Moto Stattus Ltd. | Information & communication | 2022 |