| Murano Services Ltd | Administrative & support | 2023 |
| Muren Ltd | Professional & scientific | 2025 |
| Murmuration Records Ltd | Information & communication | 2023 |
| Murphy Sawers & Peck Limited | Financial services | 2007 |
| Murphy Sawers Consulting Limited | Financial services | 2000 |
| Muscle Fuel Supplements Limited | Wholesale & retail | 2025 |
| Musgrave Consulting Ltd | Information & communication | 2024 |
| Music Connect (London) Limited | Arts & recreation | 2017 |
| Musk Fabrication & Welding Services Limited | Manufacturing | 2019 |
| Musketeer Solutions Holdings Limited | Financial services | 2024 |
| Musketeer Solutions Limited | Professional & scientific | 2005 |
| Muskham Management Company Limited | Households | 1974 |
| Musmar Ltd | Transport & logistics | 2026 |
| Musrat Limited | Professional & scientific | 2013 |
| Mustard Estate Ltd | Real estate | 2021 |
| Mustard Property Limited | Real estate | 2017 |
| Muvit Bros Ltd | Professional & scientific | 2026 |
| Muvit Media Ltd | Professional & scientific | 2025 |
| Muxlow & SON Specialist Stone Masons Ltd | Construction | 2016 |
| Muzame Ltd | Hospitality | 2021 |
| Muzano Muzano Ltd | Health & social care | 2022 |
| Muzzi Limited | Hospitality | 2020 |
| MV & SON Transport Ltd | Administrative & support | 2024 |
| MV Manufacturing Solutions Limited | Manufacturing | 2020 |
| MV Recruitment Ltd | Administrative & support | 2021 |
| MV Suite Ltd | Real estate | 2024 |
| MV Vehicle Services Ltd | Wholesale & retail | 2023 |
| Mvda Ltd | Wholesale & retail | 2026 |
| MVK Haulage Ltd | Transport & logistics | 2025 |
| MW ARB & Rail Ltd | Agriculture & fishing | 2023 |
| MW Car Services Ltd | Wholesale & retail | 2019 |
| MWD Caravan Parts & Accessories Ltd | Wholesale & retail | 2016 |
| Mweng Ltd | Professional & scientific | 2020 |
| MWH Shot Blasting Specialist Limited | Administrative & support | 2022 |
| MWM GAS & Plumbing Ltd | Construction | 2025 |
| MWS Store Ltd | Wholesale & retail | 2023 |
| MXS Media Ltd | Information & communication | 2024 |
| My Aesthetics Doctor Ltd | Health & social care | 2019 |
| My Business Cover Limited | Financial services | 2024 |
| My Communications Limited | Information & communication | 2010 |
| My Contractors (Peterborough) Ltd | Transport & logistics | 2019 |
| My Cricket Hub Ltd | Wholesale & retail | 2022 |
| My CVP Ltd | Hospitality | 2025 |
| My Digital Media Limited | Information & communication | 2023 |
| My EV Shop Ltd | Wholesale & retail | 2023 |
| My Expert Ltd | Professional & scientific | 2022 |
| My Extinction Ltd | Information & communication | 2020 |
| My Food Hub by Golden Yolk Farms Ltd | Wholesale & retail | 2025 |
| My Group Ltd | Wholesale & retail | 2019 |
| My Hire (Peterborough) Ltd | Administrative & support | 2018 |
| My Home Builders Ltd | Construction | 2017 |
| My Housing Options CIC | Hospitality | 2024 |
| My Local Letting Ltd | Real estate | 2022 |
| My Next Van Limited | Wholesale & retail | 2020 |
| My Portrait Photographer Ltd | Information & communication | 2019 |
| My Property Core Limited | Administrative & support | 2018 |
| My Puppysteps Ltd | Wholesale & retail | 2025 |
| My Store Ltd | Wholesale & retail | 2008 |
| My Valet Ltd | Administrative & support | 2025 |
| My Wedding Sitter Ltd | Professional & scientific | 2020 |
| MYA Properties Ltd | Real estate | 2025 |
| Mycandc Limited | Manufacturing | 2020 |
| Mycenary Ltd | Information & communication | 2026 |
| Mydatingpa Ltd | Professional & scientific | 2024 |
| Mykhaya Limited | Administrative & support | 2020 |
| Mylex Property Services Ltd | Construction | 2024 |
| MYM Logistics Ltd | Transport & logistics | 2017 |
| Mynextmotor Ltd | Wholesale & retail | 2017 |
| Mynxtbuy Ltd | Wholesale & retail | 2025 |
| MYP Global Group Limited | Education | 2023 |
| Mypothwari Limited | Education | 2025 |
| Myproperty Maintenance Limited | Real estate | 2023 |
| Mysolutionsuk Limited | Construction | 2024 |
| Myson Homes Ltd | Real estate | 2019 |
| Mysons Property Investments Ltd | Real estate | 2023 |
| Myspace Realty Ltd | Real estate | 2024 |
| Mysparklingservice Limited | Administrative & support | 2025 |
| Mytime Media Limited | Manufacturing | 2005 |
| Mytravel Luxembourg UK Unlimited | Professional & scientific | 2003 |
| Mytravel North America Limited | Administrative & support | 2001 |
| Mytravel Pioneer Limited | Professional & scientific | 2002 |
| Mytruckstop Limited | Other services | 2023 |
| Myvirtualsec Ltd | Administrative & support | 2026 |
| MYY Properties Ltd | Real estate | 2018 |
| MZ (Stoke) Management Ltd | Administrative & support | 2025 |
| MZ Multi Skilled Builders Ltd | Construction | 2023 |
| MZ Valley Ltd | Manufacturing | 2021 |
| MZS Holdings Limited | Administrative & support | 2017 |
| N & G Property Solutions Ltd | Real estate | 2021 |
| N & G Trans (Eastern) Ltd | Transport & logistics | 2021 |
| N & J Scott Ltd | Construction | 2005 |
| N J Metrology Limited | Information & communication | 2004 |
| N S Rickett Roofing Ltd | Construction | 2015 |
| N Y K Store Ltd | Wholesale & retail | 2022 |
| N&B Digital Ltd | Wholesale & retail | 2024 |
| N&D Group Limited | Administrative & support | 2017 |
| N&G Partitions Ltd | Construction | 2024 |
| N&M Express Ltd | Transport & logistics | 2020 |
| N&M Marketplace Limited | Wholesale & retail | 2024 |
| N&R Holdings Ltd | Professional & scientific | 2023 |