| Monawape Ltd | Manufacturing | 2023 |
| Monbuild Limited | | 1980 |
| Money Advisor Ltd | Financial services | 2018 |
| Money Smart Group Limited | Financial services | 2018 |
| Money Smart Limited | Financial services | 2014 |
| Money Tree Gadgets Ltd | Wholesale & retail | 2026 |
| Moneymakers UK Limited | Real estate | 2008 |
| Moneymosaic Ltd | Professional & scientific | 2025 |
| Monger Caravan & Resorts Limited | Hospitality | 1994 |
| Monia Catania Ltd | Wholesale & retail | 2021 |
| Monibee Limited | Extraterritorial | 2022 |
| Monika Mini Market Ltd | Wholesale & retail | 2018 |
| Monk Holdings Limited | Financial services | 2023 |
| Monkeymoo Productions Limited | Information & communication | 2014 |
| Monks Properties Limited | Real estate | 2025 |
| Monmouth Business Loans Ltd | Financial services | 2025 |
| Mono International Limited | Wholesale & retail | 2018 |
| Monoar Driving School Ltd | Education | 2026 |
| Monoceros Worldwide Limited | Real estate | 2003 |
| Monochrome Intelligence Ltd | Information & communication | 2026 |
| Monroesl Ltd | Wholesale & retail | 2025 |
| Mons Moving Motors Ltd | Transport & logistics | 2019 |
| Monsta Vapes UK Ltd | Wholesale & retail | 2026 |
| Monster Movers Limited | Transport & logistics | 2002 |
| Monster Tattoo Supplies Ltd | Other services | 2011 |
| Montana Management International Ltd | Real estate | 2025 |
| Montann Limited | Wholesale & retail | 2016 |
| Monte Carlo Cafe Limited | Hospitality | 2023 |
| Montebltn Limited | Wholesale & retail | 2024 |
| Monti UK Services Ltd | Transport & logistics | 2021 |
| MONTRAY1623 Limited | Other services | 2026 |
| Montreal Prestige Limited | Administrative & support | 2005 |
| Monty Auto Ltd | Wholesale & retail | 2024 |
| Monument Advice Ltd | Professional & scientific | 2025 |
| MOO Info SEC Ltd | Professional & scientific | 2014 |
| MOO Management Ltd | Agriculture & fishing | 2010 |
| Mood Sponge Ltd | Wholesale & retail | 2024 |
| Moody Art & Design Limited | Wholesale & retail | 2024 |
| Moon 15 Ltd | Information & communication | 2020 |
| Moon 32 Ltd | Wholesale & retail | 2026 |
| Moon Associates Limited | Professional & scientific | 2009 |
| Moon Energy Limited | Professional & scientific | 2025 |
| Moon Motorz Ltd | Transport & logistics | 2022 |
| Moon White Ltd | Wholesale & retail | 2021 |
| Moonlight Event Hire Ltd | Administrative & support | 2018 |
| Moonlight Investment ME Limited | Wholesale & retail | 2025 |
| Moonpoint Limited | Construction | 2018 |
| Moonsecurity Ltd | Administrative & support | 2020 |
| Moonshot Solutions Ltd | Information & communication | 2024 |
| Moor Connections Limited | Other services | 2021 |
| Moor Magazine Limited | Professional & scientific | 2009 |
| Moore Delivery Services (South) Limited | Transport & logistics | 2017 |
| Moore Green Recruitment Ltd | Administrative & support | 2020 |
| Moore Group Holdings Limited | Financial services | 2025 |
| Moore Influence Limited | Information & communication | 2026 |
| Moorecap Ltd | Real estate | 2021 |
| Moorewell Property Ltd | Construction | 2023 |
| Moorlands Property Extensions Ltd | Construction | 2024 |
| Moorlands Property Renovations Ltd | Construction | 2024 |
| Moorview Medical Ltd | Health & social care | 2013 |
| Moosamarket Ltd | Wholesale & retail | 2026 |
| Moove House Limited | Real estate | 2024 |
| Mopsy Limited | Arts & recreation | 2008 |
| MOR & SER Ltd | Financial services | 2024 |
| Morado Industries Ltd | Professional & scientific | 2022 |
| Morar Investments Ltd | Real estate | 2022 |
| More Fleet Ltd | Other services | 2022 |
| More Than Accountants Ltd | Professional & scientific | 2016 |
| More Track Ltd | Other services | 2022 |
| Morecambe Bay Cottages Limited | Construction | 2023 |
| Morecambe Tyre Specialists Limited | Wholesale & retail | 1993 |
| Morehustl Limited | Administrative & support | 2023 |
| Morel Consulting Limited | Administrative & support | 2022 |
| Moreland Property Development Limited | Real estate | 2021 |
| Morena Auto Parts Ltd | Wholesale & retail | 2019 |
| Morgan Care Limited | Health & social care | 2013 |
| Morgan Edwards Associates Ltd | Administrative & support | 2012 |
| Morgan Electronics Limited | Information & communication | 2004 |
| Morgan Horse Registry (PIO) Limited | Information & communication | 2003 |
| Morgan Luco Consulting Ltd | Professional & scientific | 2024 |
| Morgans Coffee Bar Ltd | Hospitality | 2024 |
| Morgans Properties (NW) Ltd | Real estate | 2025 |
| Moris Group Ltd | Administrative & support | 2023 |
| Morley Industrial Holdings Limited | Real estate | 1984 |
| Morning Rain Creative Ltd | Professional & scientific | 2025 |
| Moroccome Ltd | Administrative & support | 2025 |
| Morrell Howarth Ltd | Extraterritorial | 2016 |
| Morris & Mitchell Property Solutions Limited | Real estate | 2023 |
| Morris Green Auto's Limited | Wholesale & retail | 2021 |
| Morris Green Convenience Ltd | Wholesale & retail | 2012 |
| Morris Green Lettings Ltd | Real estate | 2023 |
| Morris Green Mini Market Limited | Wholesale & retail | 2020 |
| Morris Mini Mart Ltd | Wholesale & retail | 2018 |
| Morris Roofing NW Ltd | Construction | 2024 |
| Morrisons Enterprises Limited | Wholesale & retail | 2025 |
| Mortgage Opportunity Ltd | Professional & scientific | 2020 |
| Mortimer House RTM Company Limited | Households | 2017 |
| Mortimer Preclinical Consulting Limited | Professional & scientific | 2026 |
| Moseley Construction & Plant Hire Ltd | Administrative & support | 2024 |
| Moseley Racing Limited | Arts & recreation | 2023 |