| Moncrieff Motors Limited | Transport & logistics | 2013 |
| Moncur Medical Ltd | Health & social care | 2022 |
| Mond Group LP | | 2016 |
| Mondalius Services LP | | 2012 |
| Mondejar Ltd | Real estate | 2025 |
| Mondello Properties Ltd | Real estate | 2025 |
| Mondivo Ltd | Information & communication | 2025 |
| Mondline Transit L.P. | | 2008 |
| Mondolux L.P. | | 2013 |
| Mondor LP | | 2012 |
| Mondray Services L.P. | | 2014 |
| Mone Sales LP | | 2015 |
| Monegat LP | | 2015 |
| Moner Service Trade LP | | 2012 |
| Monetta Group Ltd | Hospitality | 2025 |
| Monetto LP | | 2015 |
| Monexo Ltd | Financial services | 2025 |
| Money Advice Partnership Ltd | Financial services | 2013 |
| Money Dashboard Ltd | Information & communication | 2006 |
| Money Station Properties (Central) Ltd | Real estate | 2019 |
| Moneyslane Finance LP | | 2012 |
| Monger Trade LP | | 2016 |
| Monica Sambo Limited | Extraterritorial | 2017 |
| Monissio Solutions LP | | 2013 |
| Monissta Trading LP | | 2013 |
| Monistar Business LP | | 2021 |
| Moniz Impex LP | | 2015 |
| Monkey Barrel Comedy Ltd | Arts & recreation | 2015 |
| Monkey Barrel Records Ltd | Manufacturing | 2020 |
| Monkey Bars (Aberdeen) Limited | Hospitality | 2009 |
| Monkey Nutz Ltd | Wholesale & retail | 2025 |
| Monkey Puzzled Holdings Limited | Financial services | 2023 |
| Monkscroft Newtown Limited | Construction | 2023 |
| Monkscroft Property Limited | Other services | 2016 |
| Monktonhall Colliery Limited | Manufacturing | 1991 |
| Monkwood MIP LP | | 2013 |
| Mono Service LP | | 2014 |
| Monoberg L.P. | | 2008 |
| Monocle Investments Ltd | Real estate | 2021 |
| Monoform Digital Ltd | Information & communication | 2026 |
| Monokeros Consulting Ltd | Information & communication | 2024 |
| Monolit Steel LP | | 2016 |
| Monovale SLP | | 1998 |
| Monower Transport L.P. | | 2010 |
| Monray Corporation LP | | 2012 |
| Monriol Solutions LP | | 2013 |
| Monroe Trading LP | | 2019 |
| Monroes Bistro Ltd | Hospitality | 2026 |
| Monsat LP | | 2011 |
| Monster Mash Cafe Ltd. | Hospitality | 2003 |
| Monster Media Ltd | Information & communication | 2021 |
| Monster Property Ltd | Real estate | 2025 |
| Monstrous Regiment Publishing Ltd | Information & communication | 2018 |
| Monsul Labs Ltd | Information & communication | 2023 |
| Montagu Bakery Limited | Manufacturing | 2013 |
| Montagu GP Commitment LP | | 2015 |
| Montagu IV (Scots Feeder) LP | | 2011 |
| Montagu Team Co-Invest LP | | 2011 |
| Montagu V (Scots Feeder) LP | | 2015 |
| Montagu VI (US) L.P. | | 2019 |
| Montague Solutions LP | | 2013 |
| Montana Union LP | | 2014 |
| Montanaro European Smaller Companies Trust PLC | Financial services | 1981 |
| Montauk (UK) Investment Holdings Limited | Financial services | 2016 |
| Montaut Limited | Real estate | 2024 |
| Montay Prestige LP | | 2013 |
| Montazhspetstroy LP | | 2015 |
| Montblanc Consulting Ltd | Professional & scientific | 2022 |
| Montbridge L.P. | | 2013 |
| Montburg Services LP | | 2015 |
| Monte Blanco SP | | 2005 |
| Monte Carbo LP | | 2015 |
| Monteadriatic Developments Ltd | Financial services | 2018 |
| Montealegere LP | | 2008 |
| Montebasso LP | | 2015 |
| Montedin Ltd | Information & communication | 2018 |
| Montedo Trade LP | | 2015 |
| Monteith & Monteith Partnership | | 1998 |
| Monteith Personal Care Management Limited | Health & social care | 2015 |
| Montelimar SP | | 2000 |
| Monteneo Trading LP | | 2017 |
| Monteri Group LP | | 2018 |
| Monterosa Corp LP | | 2014 |
| Montes LP | | 2010 |
| Montessori Methods Ltd | Education | 2012 |
| Monteverdi LP | | 2006 |
| Montferrer LP | | 2012 |
| Montfort Impex LP | | 2012 |
| Montgo Services Ltd | Professional & scientific | 2013 |
| Montgomery & Montgomery Partnership | | 1998 |
| Montgomery Real Estate Ltd | Real estate | 2016 |
| Montgomery Valley Investments Ltd | Real estate | 2017 |
| Montgomery Vision Limited | Health & social care | 2002 |
| Montgowell LP | | 2016 |
| Montpelier Consulting Ltd | Professional & scientific | 2014 |
| Montpelier Inns Limited | Hospitality | 1994 |
| Montpeliers (Edinburgh) Holdings Ltd | Hospitality | 2021 |
| Montpeliers (Edinburgh) Limited | Hospitality | 1996 |
| Montreal Property Ltd | Real estate | 2014 |
| Montree Management Ltd | Real estate | 2024 |