| Meadway Roofing Ltd | Construction | 2025 |
| Mean London Ltd | Wholesale & retail | 2018 |
| Mean Street Tattoo Parlour Limited | Administrative & support | 2016 |
| Meantime Media Ltd | Information & communication | 2008 |
| Measured UP Consulting Ltd | Professional & scientific | 2016 |
| Meat & Beer Company Ltd | Professional & scientific | 2016 |
| Meat the Fish Lease Limited | Hospitality | 2018 |
| Meats & Chips Ltd | Hospitality | 2025 |
| Meaty Fish Limited | Wholesale & retail | 2013 |
| Meazey Search Ltd | Professional & scientific | 2024 |
| MEC Consulting Ltd | Information & communication | 2014 |
| Mech-A-Tech Services Ltd | Manufacturing | 2024 |
| Mechanical Plant Selection Ltd | Professional & scientific | 2024 |
| Mechaspritz Limited | Professional & scientific | 2007 |
| Mechway Limited | Wholesale & retail | 2021 |
| MED2 Bar (Norwich) Limited | Hospitality | 2023 |
| Medhaven Financial Planning Ltd | Professional & scientific | 2023 |
| Media & Crisis Management Ltd | Administrative & support | 2000 |
| Media ROC Ltd | Information & communication | 2023 |
| Media, Film and Television for International Students Limited | Education | 2024 |
| MEDIACONTRACTS(2012) Limited | Information & communication | 2012 |
| Mediad Ltd | Information & communication | 2012 |
| Mediapro Media Training Limited | Professional & scientific | 2004 |
| Mediation 1ST Limited | Professional & scientific | 2020 |
| Medical Concierge International Ltd | Extraterritorial | 2016 |
| Medical Contact Services Limited | Administrative & support | 2003 |
| Medical Holdings Ltd | Extraterritorial | 2022 |
| Medical Pharma Projects Limited | Professional & scientific | 2021 |
| Medical Service Solutions (GB) Ltd | Health & social care | 2018 |
| Medicap Services Ltd | Health & social care | 2021 |
| Mediceutics Ltd | Manufacturing | 2021 |
| Medicorp Ltd | Health & social care | 2013 |
| Medidesk Ltd | Administrative & support | 2026 |
| Medieval Masonry Ltd | Construction | 2014 |
| Medina (Norwich) Limited | Hospitality | 2013 |
| Medina Plastic Surgery Limited | Health & social care | 2020 |
| Medisingh Care Ltd | Health & social care | 2023 |
| Medismart Technologies Ltd | Manufacturing | 2017 |
| Mediswift Logistics Ltd | Transport & logistics | 2025 |
| Meditation Personal Trainers Ltd | Health & social care | 2023 |
| Mediterranean Boucherie Ltd | Wholesale & retail | 2013 |
| Medler Turf Limited | Administrative & support | 2019 |
| Medoffice SSC Limited | Health & social care | 2022 |
| Medoffice SVW Limited | Wholesale & retail | 2022 |
| Medsio Holdings Limited | Financial services | 2015 |
| Medsio Limited | Wholesale & retail | 2005 |
| Medway Norse Limited | Administrative & support | 2013 |
| Medway Norse Transport | Transport & logistics | 2014 |
| Medway Premier Lettings.Com Ltd | Real estate | 2008 |
| Meera Fashion Limited | Wholesale & retail | 2025 |
| Meera Foodz Ltd | Hospitality | 2022 |
| Meeres Limited | Administrative & support | 2015 |
| Meerkat Project Management Ltd | Information & communication | 2016 |
| Meermin UK Ltd | Wholesale & retail | 2023 |
| Meert Financial Consulting Ltd | Professional & scientific | 2012 |
| Mees Solutions Limited | Professional & scientific | 2017 |
| MEG Kebabs Limited | Hospitality | 2019 |
| Mega Pizza Kebab Ltd | Hospitality | 2025 |
| Megazone (Leicester) Limited | Arts & recreation | 2011 |
| Megstetics Ltd | Other services | 2026 |
| Mehuz Shop Ltd | Wholesale & retail | 2026 |
| Mejana Limited | Hospitality | 2022 |
| MEL Newton Dog Training Ltd | Other services | 2023 |
| Meld Audio Limited | Information & communication | 2022 |
| Meliora Minds Ltd | Health & social care | 2022 |
| Melissa Clarke Therapy Ltd | Health & social care | 2025 |
| Melissa Epifano Limited | Other services | 2022 |
| Melit Palathingal Health Care Ltd | Health & social care | 2022 |
| Melius Innovations Limited | Agriculture & fishing | 2024 |
| Mellow Enterprises Ltd | Administrative & support | 2012 |
| Melody Belle Ltd | Other services | 2022 |
| Melsima Care Services Ltd | Health & social care | 2014 |
| Melton Builders of Beetley Limited | Construction | 2009 |
| Melton Grange Management Company Limited | Households | 2008 |
| Melton Project Consultancy Limited | Professional & scientific | 2011 |
| Melton Tyre and Exhaust Centre Limited | Wholesale & retail | 1981 |
| Melville Hall Hotel Limited | Hospitality | 2017 |
| Melvin Sparrow Limited | Construction | 2003 |
| Memjo Limited | Information & communication | 2018 |
| Memories 2 Treasure Photography Limited | Professional & scientific | 2012 |
| Memory.Net Ltd | Health & social care | 2016 |
| MEN Tally UP Ltd | Administrative & support | 2021 |
| Mena Trade Limited | Wholesale & retail | 2019 |
| Menck UK Limited | Professional & scientific | 2024 |
| Menissez Bakery Group UK Limited | Manufacturing | 2026 |
| Mennaye Medical Ltd | Health & social care | 2022 |
| Menopause Money Limited | Administrative & support | 2025 |
| Menopause Support Community Interest Company | Administrative & support | 2019 |
| Mens Fashion Magazine Limited | Professional & scientific | 2024 |
| Mental Health Change Ltd | Education | 2021 |
| Mentality Matters Limited | Extraterritorial | 2017 |
| Mentmore Way NO.1 Management Company Limited | Real estate | 2016 |
| Mentor Consulting Limited | Real estate | 2009 |
| Meraki Project Management Limited | Other services | 2022 |
| Meraki Social Limited | Professional & scientific | 2022 |
| Mercado DA Saudade Ltd | Wholesale & retail | 2018 |
| Mercantem Limited | Real estate | 2016 |
| Mercantile Trust Limited | Financial services | 2009 |
| Mercantile Trust Syndicate Number One Limited | Financial services | 2024 |
| Mercatino Norwich Ltd | Wholesale & retail | 2025 |