| Momo Club Ltd | Hospitality | 2019 |
| Momo Indo Trading Ltd | Administrative & support | 2023 |
| Momz Love Limited | Wholesale & retail | 2020 |
| MON Abri Investments Ltd | Real estate | 2021 |
| Mona's Catering Ltd | Hospitality | 2019 |
| Monaman Limited | Professional & scientific | 1993 |
| Monarch Consultancy Services Ltd | Professional & scientific | 2026 |
| Monarch East Limited | Hospitality | 2013 |
| Monarch Property Developments Limited | Real estate | 2025 |
| Monarch's Walk (Clanfield) Management Company Limited | Households | 2014 |
| Monate Limited | Arts & recreation | 2011 |
| Monchelsea Park (Bicknor House) Management Company Limited | Households | 2021 |
| Monchelsea Park (Sutton House) Management Company Limited | Households | 2021 |
| Monchelsea Park Management Company Limited | Households | 2020 |
| Moncherri Ltd | Manufacturing | 2025 |
| Monday Media Ltd | Professional & scientific | 2026 |
| Mondo Edile Ltd | Construction | 2020 |
| Monetize Mastery Limited | Information & communication | 2025 |
| Money Saving Parent Limited | Financial services | 2025 |
| Moneywell Services Ltd | Professional & scientific | 2026 |
| Mongolian Yurts Direct Limited | Wholesale & retail | 2008 |
| Mongoose Clothing Limited | Wholesale & retail | 2019 |
| Moni Future Ltd | Transport & logistics | 2019 |
| Moni 2002 Ltd | Transport & logistics | 2025 |
| Monic Polymer Ltd | Wholesale & retail | 2018 |
| Monika&Lukas "Syrena" Ltd | Hospitality | 2019 |
| Monikos Ltd | Wholesale & retail | 2023 |
| Monimixup Ltd | Wholesale & retail | 2026 |
| Monmal Limited | Professional & scientific | 2025 |
| Monoflows Ltd | Information & communication | 2022 |
| Monsoon Property Ltd | Real estate | 2016 |
| Monster Property Services UK Ltd | Construction | 2015 |
| Monsters Music Ltd | Wholesale & retail | 2020 |
| Montacute Mews Management Limited | Households | 2006 |
| Montague (Guild Street) Freehold Limited | Households | 2017 |
| Montague (Guild Street) Management Company Limited | Households | 2000 |
| Montague House (Worthing) Management Company Limited | Households | 2001 |
| Montague Place Management Limited | Households | 2010 |
| Montana Business Solutions Ltd | Information & communication | 2012 |
| Montevetro Management Company Limited | Households | 1997 |
| Montfort Gate Management Company Limited | Households | 2008 |
| Montgomery Gardens Management Company Limited | Households | 2004 |
| Montgomery House Management Company Limited | Households | 1974 |
| Monument Music Limited | Financial services | 2025 |
| Monxie UK Ltd | Wholesale & retail | 2021 |
| Moodlit&Co Limited | Wholesale & retail | 2020 |
| Moody's Munchies Limited | Hospitality | 2017 |
| Moon and the Sea Limited | Arts & recreation | 2024 |
| Moon Awakening Ltd | Other services | 2024 |
| Moon Capital Systems Ltd | Financial services | 2025 |
| Moon Entertainment Systems Ltd | Information & communication | 2023 |
| Moon Infotech Ltd | Information & communication | 2026 |
| Moondra Ltd | Hospitality | 2025 |
| Moonlight (UK) Limited | Wholesale & retail | 2013 |
| Moonlight Clothing and Bags Limited | Wholesale & retail | 2024 |
| Moonlight Events & Lola Frozen Foods Limited | Hospitality | 2011 |
| Moonlightj Ltd | Wholesale & retail | 2023 |
| Moor Green Lane Management Company Limited | Households | 2014 |
| Moor Hall Park (Ninfield) Management Company Limited | Households | 2026 |
| Moore & Partners Estates Limited | Real estate | 2013 |
| Moore Clean Services Ltd | Administrative & support | 2024 |
| Moore Future - Embrace the Journey Ltd | Health & social care | 2025 |
| Moores Associates Limited | Professional & scientific | 2009 |
| Moores Contracts Limited | Construction | 2025 |
| Moores Projects Limited | Construction | 2016 |
| Moorland Spring Meadows Management Limited | Households | 2004 |
| Moorside Court Management Limited | Households | 2001 |
| Moothon Limited | Real estate | 2021 |
| Mora the Reef Ltd | Real estate | 2024 |
| Morango Creative Ltd | Professional & scientific | 2018 |
| Mordan Words Limited | Real estate | 2017 |
| Morden Pharma Ltd | Wholesale & retail | 2026 |
| Morden Traders Ltd | Wholesale & retail | 2023 |
| More Than a Parent C.I.C. | Hospitality | 2026 |
| More Than Post Limited | Transport & logistics | 2015 |
| More's Garden Management Limited | Households | 1982 |
| Morello Maintenance Ltd | Manufacturing | 2025 |
| Morelock Online Limited | Manufacturing | 2023 |
| Moretime Music Limited | Wholesale & retail | 2019 |
| Moretime Properties Limited | Real estate | 2021 |
| Morgan and Ashley Investment Limited | Construction | 2019 |
| Morgan Smith Immigration Ltd | Administrative & support | 2017 |
| Morgan Styles LLP | | 2011 |
| Morgane & Co Builders Limited | Construction | 2019 |
| Morland Enterprises Limited | Real estate | 2022 |
| Morland Tatry Ltd | Real estate | 2026 |
| Morleys South Croydon Ltd | Hospitality | 2026 |
| Mormor Ltd | Real estate | 2026 |
| Mornington Flats Management Company Limited | Households | 1992 |
| Morocargo UK Limited | Professional & scientific | 2001 |
| Morris and Co Lettings Ltd | Real estate | 2023 |
| Morris Way Freehold Company Limited | Households | 1998 |
| Mortada Limited | Hospitality | 2014 |
| Mortigo Ltd | Financial services | 2020 |
| Mortimers Commercial Limited | Real estate | 2008 |
| Mortimers Surveys Limited | Professional & scientific | 2013 |
| Morton - Fairview Electrical Services Limited | Construction | 1972 |
| Morton Court Management Limited | Households | 1981 |
| Mosaic Holidays Limited | Administrative & support | 1986 |
| Mosbridge Travel and Holiday Ltd | Administrative & support | 2025 |