| Me&P Property Services Limited | Real estate | 2017 |
| Meade New Homes Ltd | Real estate | 2020 |
| Meadow View (Pamber END) Management Co Limited | Households | 2023 |
| Meadowcity Property Management Company Limited | Households | 1991 |
| Meadows Title Limited | Professional & scientific | 2016 |
| Mealfuarvonie PM Ltd | Professional & scientific | 2020 |
| Mediateuk Ltd | Professional & scientific | 2022 |
| Medical Professional Services Limited | Health & social care | 2022 |
| Medics-Uk Limited | Health & social care | 2016 |
| Medina Capital Dairy Company Limited | Wholesale & retail | 2009 |
| Medina Freshways Holdings Ltd | Professional & scientific | 2021 |
| Medsurg Elective Care Limited | Health & social care | 2025 |
| Medtron Limited | Health & social care | 2023 |
| Meemo Industries Limited | Information & communication | 2017 |
| MEG Bowen Solutions Limited | Administrative & support | 2015 |
| Megalo Recruit Ltd | Other services | 2020 |
| Mehdi Heatherside Limited | Hospitality | 2025 |
| Melanie Downing Interiors Limited | Manufacturing | 2014 |
| Melena Ltd | Real estate | 2022 |
| Melita & Cowper Ltd | Construction | 2022 |
| Mellaris Ltd | Wholesale & retail | 2006 |
| Mellefont Residents Association Limited | Households | 1982 |
| Melody Andy Limited | Real estate | 2023 |
| MEM Investment Limited | Hospitality | 2020 |
| Memco Framing Limited | Professional & scientific | 2020 |
| Memco Memorabilia Limited | Other services | 2025 |
| Memiah Limited | Information & communication | 2005 |
| Mencigar Ltd | Wholesale & retail | 2025 |
| Menhir Home Limited | Transport & logistics | 2022 |
| Meon View Management Company Limited | Households | 2021 |
| Meqyamo Limited | Real estate | 2006 |
| Mercury Electroplating Limited | Manufacturing | 2004 |
| Mercury Plating Services Ltd | Extraterritorial | 2009 |
| Merlins the Jewellers Limited | Wholesale & retail | 2012 |
| Mermicorn Limited | Real estate | 2023 |
| Merrist Wood Golf Club Limited | Arts & recreation | 1996 |
| Merritt Developments Limited | Construction | 1985 |
| Merritt Homes South East Limited | Construction | 1996 |
| Merrow Grange Residents Limited | Households | 1994 |
| Messheads Hair Design Ltd | Other services | 2012 |
| Metal Shapes & Pressings Limited | Manufacturing | 1998 |
| Metavigilance Ltd | Professional & scientific | 2022 |
| Meter Corp 3 Limited | Administrative & support | 2020 |
| Meter Corp 4 Limited | Administrative & support | 2020 |
| Meter Corp Ltd | Administrative & support | 2015 |
| Methley Fitout Services Limited | Construction | 2014 |
| Methley Installations Ltd | Construction | 2010 |
| Meticulous Groundworks Ltd | Construction | 2024 |
| Metis Search Ltd | Other services | 2016 |
| Metro (Guildford) Management Company Limited | Households | 2006 |
| Metro and Green Limited | Real estate | 2008 |
| Metropolitan City Investments Limited | Real estate | 2015 |
| Mexicali Food Truck Limited | Hospitality | 2023 |
| Meykaya UK International Limited | Wholesale & retail | 2012 |
| MFC Management Limited | Real estate | 2000 |
| MFK Studios Ltd | Information & communication | 2026 |
| MG Logistical Ltd | Information & communication | 2020 |
| MG Prestige Wide Ltd | Wholesale & retail | 2020 |
| MG Tech Ltd | Wholesale & retail | 2021 |
| MGF Legal Services Limited | Professional & scientific | 2021 |
| MHC Consulting Ltd | Professional & scientific | 2020 |
| Michael Usher Estate Agents Ltd | Real estate | 2016 |
| Michael Usher Mortgage Services Limited | Financial services | 2001 |
| Michael Usher Property Services Ltd | Real estate | 2015 |
| Microtek Limited | Wholesale & retail | 1999 |
| Midas DC Limited | Professional & scientific | 2024 |
| Midasquest Limited | Information & communication | 2013 |
| Midasys Technologies Ltd | Information & communication | 2023 |
| Middle Gordon Road Properties Limited | Real estate | 2017 |
| Middlesex Property Management Limited | Real estate | 1988 |
| Midgley Consulting Ltd | Administrative & support | 2009 |
| Midnight Carpentry & Joinery Limited | Wholesale & retail | 1999 |
| Miit Ltd | Extraterritorial | 2023 |
| Mike Beck Design Ltd | Professional & scientific | 2019 |
| Mike Frost Carpets Limited | Construction | 2016 |
| Mike Knight Management Limited | Administrative & support | 1989 |
| Mike P Partnerships LLP | | 2023 |
| Mike Plant Ltd | Information & communication | 2023 |
| Mike Speller Construction Limited | Administrative & support | 2014 |
| MIL Management Company Ltd. | Households | 2015 |
| Milano 57 Ltd | Hospitality | 2022 |
| Milebury Solutions Limited | Information & communication | 2015 |
| Miles & Forbes Ltd | Professional & scientific | 2020 |
| Milford Golf Property Limited | Real estate | 2020 |
| Milford Operations Limited | Arts & recreation | 2020 |
| Milford Rail and Engineering Services Limited | Administrative & support | 2024 |
| Milk and Marula Limited | Wholesale & retail | 2026 |
| Millbridge Brickwork Ltd | Construction | 2013 |
| Millivivash Limited | Real estate | 2021 |
| Millstone Court Management Company Limited | Households | 2015 |
| Milly Cleaning UK Limited | Administrative & support | 2019 |
| Milo Legal Ltd | Professional & scientific | 2022 |
| Mind Minders Psychology Center Ltd | Health & social care | 2016 |
| Minden Court Management Company Limited | Households | 2016 |
| Mindfunk Limited | Arts & recreation | 2026 |
| Mine&Co Ltd | Professional & scientific | 2026 |
| Minekeep Limited | Construction | 1985 |
| Mingley Camberley Ltd | Hospitality | 2023 |
| Mingvest Deals Ltd | Real estate | 2025 |
| Mingvest Ltd | Real estate | 2024 |