| Modern China Whole Sale Ltd | Wholesale & retail | 2024 |
| Modern Finance Ltd | Extraterritorial | 2017 |
| Modern Money Guru Ltd | Information & communication | 2025 |
| Modern Organic Home Limited | Wholesale & retail | 2024 |
| Modern Web Solutions Limited | Information & communication | 2024 |
| Modest Enterprises Ltd | Real estate | 2020 |
| Modfin Ltd | Information & communication | 2021 |
| Modfits Ltd | Wholesale & retail | 2026 |
| Modge Limited | Administrative & support | 2017 |
| Modglass (South Yorkshire) Limited | Construction | 2001 |
| Modhides Company Ltd | Wholesale & retail | 2025 |
| Modhu Mitha Restaurant Ltd | Hospitality | 2013 |
| Modriver Ltd | Transport & logistics | 2026 |
| Moduform Living Limited | Wholesale & retail | 2025 |
| Modular Group Limited | Administrative & support | 2009 |
| Modular Heat Exchangers Limited | Administrative & support | 2009 |
| Modular Limited | Administrative & support | 2009 |
| Modular Scaffolding & Building Equipment Limited | Construction | 1980 |
| Modulo Consulting Ltd | Professional & scientific | 2023 |
| Modus Contractors Ltd | Construction | 2026 |
| Modus Group Ltd | Construction | 2026 |
| Modus Tollens Ltd | Wholesale & retail | 2025 |
| Moeschle (UK) Limited | Manufacturing | 2002 |
| Moff Sales Limited | Wholesale & retail | 2023 |
| Moffatrocity Limited | Households | 2021 |
| Mohammed Sharif Medical Ltd | Health & social care | 2019 |
| Mohan Properties Limited | Real estate | 2020 |
| Mohil Properties Ltd | Construction | 2021 |
| Mohl 4 Ltd | Health & social care | 2024 |
| Mohl 5 Ltd | Health & social care | 2024 |
| Mohl 6 Ltd | Health & social care | 2025 |
| Mohl 7 Ltd | Health & social care | 2025 |
| Mohy Properties Ltd | Real estate | 2026 |
| Moira Lane Limited | Construction | 2024 |
| Mojisola Kareem Studios Ltd | Information & communication | 2026 |
| Mojo Property Holdings Ltd | Real estate | 2025 |
| Mokho PR Limited | Professional & scientific | 2021 |
| Mokijo Limited | Information & communication | 2013 |
| Mokimo Limited | Professional & scientific | 2026 |
| Mola Healthcare Ltd | Health & social care | 2020 |
| Molfin Limited | Hospitality | 2013 |
| Molinor Limited | Manufacturing | 1999 |
| Mollaya Property Ltd | Real estate | 2026 |
| Mollitium Private Equity Limited | Professional & scientific | 2017 |
| Molly Limpet's Theatrical Emporium Limited | Arts & recreation | 2001 |
| Molly Malone's Derby Limited | Hospitality | 2024 |
| Molly Molly Ltd | Wholesale & retail | 2024 |
| Molly's Cafe and Deli Ltd | Hospitality | 2021 |
| Molly's Irish Bar (Molly's Group) Ltd | Hospitality | 2023 |
| Molly's Irish Bar Limited | Hospitality | 2020 |
| Mollys Booth Derby Limited | Professional & scientific | 2026 |
| Mollyteck Ltd | Wholesale & retail | 2021 |
| Molmet Limited | Wholesale & retail | 2018 |
| Moloi Ltd | Other services | 2025 |
| Momba Limited | Health & social care | 2018 |
| Moment Skincare Limited | Wholesale & retail | 2023 |
| Momenzo Ltd | Information & communication | 2017 |
| Momma Katz Ltd | Hospitality | 2023 |
| Momo Auto Service Ltd | Wholesale & retail | 2025 |
| Momo Food Ltd | Hospitality | 2026 |
| Momo Jewellers Ltd | Wholesale & retail | 2025 |
| Momo Machi Ltd | Wholesale & retail | 2025 |
| Momos Barber Ltd | Other services | 2026 |
| Monaghans EOT Trustees Limited | Administrative & support | 2025 |
| Monaghans Investments Limited | Other services | 2025 |
| Monaghans Limited | Professional & scientific | 2007 |
| Monarch Gardens & Landscaping LLP | | 2015 |
| Monarch Travels Ltd | Administrative & support | 2026 |
| Monarch Turnkey Solutions Ltd | Professional & scientific | 2025 |
| Monarchs Gate (ST Andrews) Management Company Limited | Households | 2003 |
| Monash Ltd | Professional & scientific | 2015 |
| Monckton Developments Limited | Real estate | 2017 |
| Monedela Ltd | Information & communication | 2026 |
| Money KNG Ltd | Wholesale & retail | 2023 |
| Mongevity Limited | Administrative & support | 2002 |
| Monica's at FOX Valley Ltd | Wholesale & retail | 2024 |
| Monkey Powders Ltd | Construction | 2026 |
| Monkey Socks Limited | Arts & recreation | 2016 |
| Monks Clothing Limited | Wholesale & retail | 2026 |
| Monksbridge Garage Ltd | Wholesale & retail | 2015 |
| Monoclinic Limited | Professional & scientific | 2019 |
| Monogram Cutlery Co Limited | Extraterritorial | 1992 |
| Monotone Studios Limited | Professional & scientific | 2017 |
| Monotones Entertainment Ltd | Arts & recreation | 2018 |
| Mons Martis Limited | Real estate | 2013 |
| Mont Blanc Treks Limited | Arts & recreation | 2011 |
| Mont Jake Limited | Information & communication | 2016 |
| Montagu 406 Regeneration LLP | | 2018 |
| Montagu Property Services (South West) Limited | Construction | 2014 |
| Montagu West Human Capital Limited | Administrative & support | 2015 |
| Montague European Investments Limited | Other services | 2006 |
| Montari Interiors Ltd | Wholesale & retail | 2025 |
| Monteros Finance Limited | Financial services | 2013 |
| Monteros SUB Co 1 Limited | Financial services | 2014 |
| Monteros SUB Co 2 Limited | Extraterritorial | 2014 |
| Montgomery Collection Limited | Manufacturing | 1998 |
| Montgomery Court Flats Company Limited | Households | 1980 |
| Montgomery House Medical Centre | Health & social care | 1963 |
| Montgomery Property Management Limited | Professional & scientific | 1990 |
| Montgomery Stokes Ltd | Extraterritorial | 2023 |