| MMM Residential and Commercial Ltd | Real estate | 2026 |
| MMO Pharma Ltd | Health & social care | 2009 |
| MMR Venture Holdings Ltd | Financial services | 2026 |
| Mmut Ltd | Transport & logistics | 2021 |
| MMW Couriers Ltd | Extraterritorial | 2020 |
| Mmxm Ventures Ltd | Transport & logistics | 2023 |
| MN Freight Services Limited | Transport & logistics | 2023 |
| Mn&N Electrical Ltd | Construction | 2018 |
| MNC Partners Ltd | Agriculture & fishing | 2026 |
| Mngbg Commercial Ltd | Transport & logistics | 2022 |
| MNM Transport Ltd | Transport & logistics | 2021 |
| MNS Developments Limited | Wholesale & retail | 2017 |
| Mntargets Ltd | Construction | 2024 |
| Mntm Utility Solutions Ltd. | Administrative & support | 2013 |
| MO Catering Ltd | Hospitality | 2024 |
| Mobile JET Wash Solutions Ltd | Administrative & support | 2020 |
| Mobile Fabrication Services Limited | Manufacturing | 2015 |
| Mobile in Car (UK) Ltd | Wholesale & retail | 2015 |
| Mobile Merch Solutions Limited | Manufacturing | 2019 |
| Mobile Units Ltd | Wholesale & retail | 2018 |
| Mobile Zone Norfolk Ltd | Wholesale & retail | 2023 |
| Mobilek Ltd | Transport & logistics | 2025 |
| Mobilezone Peterborough Limited | Wholesale & retail | 2015 |
| Mobin Courier Limited | Transport & logistics | 2018 |
| Mockology Ltd | Hospitality | 2025 |
| Moda Building Ltd | Construction | 2020 |
| Modco Limited | Wholesale & retail | 1998 |
| Model Theory Limited | Administrative & support | 2024 |
| Modern Dentistry Centre Ltd | Health & social care | 2021 |
| Modern Iconic Team Limited | Real estate | 2023 |
| Modern Nest Solutions Ltd | Wholesale & retail | 2025 |
| Modern Standard Homes Ltd | Real estate | 2020 |
| Modha Swift Community Health Ltd | Health & social care | 2024 |
| Modir Cloud Ltd | Information & communication | 2026 |
| Modo Electrical Services Ltd | Construction | 2025 |
| MODULE8 Consultancy Limited | Construction | 2020 |
| Modus Healthcare Ltd | Public administration | 2020 |
| Modus Online Limited | Arts & recreation | 2020 |
| Modus Vita Health Ltd | Health & social care | 2026 |
| Mohamed Ashiqur Rahman Ltd | Extraterritorial | 2022 |
| Moica Group Ltd | Professional & scientific | 2024 |
| Moisey Computing Limited | Information & communication | 1997 |
| Mojo Hair & Beauty Limited | Other services | 2003 |
| Mojonas Management Ltd | Information & communication | 2014 |
| Molconkie Property Ltd | Real estate | 2015 |
| Moldo Services Ltd | Transport & logistics | 2018 |
| Molo Properties Ltd | Real estate | 2024 |
| Momentum Psychology Limited | Health & social care | 2015 |
| Momentum Vehicle Servicing Ltd | Wholesale & retail | 2019 |
| Momod Ltd | Information & communication | 2010 |
| Monar Ltd | Transport & logistics | 2022 |
| Monarch Peterborough Holdings Limited | Real estate | 2021 |
| Monarch Services Limited | Real estate | 2005 |
| Monarch Traders Limited | Wholesale & retail | 2025 |
| Monaughty Farms Limited | Agriculture & fishing | 1996 |
| Mondago Holdings Limited | Information & communication | 2014 |
| Mondago Limited | Information & communication | 2000 |
| Mondair Construction Limited | Construction | 2021 |
| Mondair Estates Limited | Real estate | 2017 |
| Monet Studios Ltd | Wholesale & retail | 2022 |
| Monetizze Capital Finance Ltd | Financial services | 2025 |
| Money Talks Accountancy Services Limited | Professional & scientific | 2011 |
| Money Talks Ltd | Professional & scientific | 2019 |
| Moneywise Motors Ltd | Wholesale & retail | 2023 |
| Moni GRO Ltd | Information & communication | 2024 |
| MONI24CARE Limited | Health & social care | 2023 |
| Monikaink Limited | Other services | 2023 |
| Monksmoor Park C.I.C. | Households | 2014 |
| Monkswood Communications Ltd | Information & communication | 2016 |
| Mono Marketing Ltd | Wholesale & retail | 2018 |
| Monoline Studio Ltd | Professional & scientific | 2021 |
| Monster 4X4 Ltd | Wholesale & retail | 2019 |
| Monta Auto Inspect Ltd | Information & communication | 2025 |
| Montague Property Limited | Real estate | 2018 |
| Montaure Atelier Limited | Wholesale & retail | 2026 |
| Montclair Property Group Ltd | Real estate | 2026 |
| Montem Holdings Ltd | Financial services | 2024 |
| Montem Ltd | Real estate | 2019 |
| Monteska Ltd | Transport & logistics | 2016 |
| Montex Commercial Ltd | Wholesale & retail | 2023 |
| Montex Properties UK Ltd | Real estate | 2026 |
| Montfalcon Limited | Professional & scientific | 2005 |
| Montrose Worldwide Limited | Transport & logistics | 2016 |
| Montsoko Limited | Manufacturing | 2022 |
| Monument Dental Studio Ltd | Health & social care | 2020 |
| Moocake Ltd | Manufacturing | 2024 |
| Moodscope Limited | Administrative & support | 2009 |
| Moon Courier Ltd | Transport & logistics | 2019 |
| Moon Iris Ltd | Health & social care | 2025 |
| Moonlight Fast Foods Ltd | Hospitality | 2014 |
| Moons Solicitors Ltd | Professional & scientific | 2023 |
| Moonstone Rentals Limited | Other services | 2021 |
| Moonstrike Capital Ltd | Financial services | 2022 |
| Moor Farm Shop and Catering Limited | Wholesale & retail | 2018 |
| Moore Construction Consultants Ltd | Construction | 2025 |
| Moore Extras Limited | Other services | 2022 |
| MOR 2024 Limited | Wholesale & retail | 2024 |
| More Commercial Ltd | Financial services | 2025 |
| More Muzic Radio CIC | Arts & recreation | 2022 |
| Morena 91 Ltd | Transport & logistics | 2025 |