| Medistaff Limited | Administrative & support | 2016 |
| Mediterranean Staff Consultancy Limited | Wholesale & retail | 2022 |
| Mediterranevm Group Ltd | Professional & scientific | 2019 |
| Mediumrare Ltd | Professional & scientific | 2018 |
| Medix & Carers Ltd | Health & social care | 2025 |
| Medj Scaffolding Ltd | Construction | 2023 |
| MEDLEGAL70 Ltd | Health & social care | 2023 |
| Medley Marine Limited | Professional & scientific | 2015 |
| Medops Connect Ltd | Professional & scientific | 2026 |
| Medrevision Ltd | Education | 2018 |
| Medsally Healthcare Ltd | Health & social care | 2017 |
| Medsci Consulting Limited | Health & social care | 2017 |
| Medserve (South West) Ltd | Health & social care | 2001 |
| Medsina Ltd | Health & social care | 2025 |
| Medspark Limited | Health & social care | 2023 |
| Medtech Plus Limited | Health & social care | 2011 |
| Medtek Group Ltd | Health & social care | 2025 |
| Medusa Stonemasonry Limited | Administrative & support | 2004 |
| Medworks Services Limited | Professional & scientific | 2017 |
| Medxquality Services Ltd | Professional & scientific | 2025 |
| Meech Media Limited | Information & communication | 2011 |
| Meehan & Co Consulting Ltd | Professional & scientific | 2016 |
| Meels PT Limited | Arts & recreation | 2022 |
| Meem Real Estate Ltd | Real estate | 2025 |
| Meena Colors UK Ltd | Wholesale & retail | 2026 |
| Meerkat Capital Ltd | Financial services | 2012 |
| Meet and Greet A38 Bristol Airport Ltd | Hospitality | 2020 |
| Meet the Boss Limited | Administrative & support | 2013 |
| Meeting Place Communications Ltd | Professional & scientific | 2011 |
| Meetings & Incentives Europe Ltd | Administrative & support | 2013 |
| Meeza Technologies Ltd | Information & communication | 2026 |
| MEF Plumbing & Heating Limited | Construction | 2015 |
| MEG Globa Limited | Manufacturing | 2026 |
| Mega Jump Limited | Arts & recreation | 2015 |
| Mega Market U.K Ltd | Wholesale & retail | 2025 |
| Mega Musical Bingo Ltd | Information & communication | 2013 |
| Mega Pixels Ltd | Professional & scientific | 2014 |
| Mega Save Bristol Limited | Wholesale & retail | 2025 |
| Mega-Mega Ltd | Professional & scientific | 2017 |
| Mega-Rod Limited | Extraterritorial | 2016 |
| Mega-Ud Consulting Ltd | Professional & scientific | 2023 |
| Megaverse Ltd | Professional & scientific | 2018 |
| Megg Interiors Ltd | Professional & scientific | 2022 |
| Meghna Bristol Ltd | Hospitality | 2020 |
| Megit Group Limited | Information & communication | 2020 |
| Megit Properties Limited | Real estate | 2020 |
| Megna Catering Ltd | Hospitality | 2018 |
| Mehmood Trading Ltd | Wholesale & retail | 2023 |
| Mehta 22 Investments Limited | Real estate | 2014 |
| Mehta Ukbrothers Limited | Real estate | 2016 |
| Mehzie Limited | Health & social care | 2019 |
| Meidenform LP | | 2011 |
| Meijia Ltd | Construction | 2025 |
| Meili Events Ltd | Professional & scientific | 2023 |
| Meili Productions Limited | Information & communication | 2014 |
| Meinfame LP | | 2013 |
| Meishicha Ltd | Hospitality | 2023 |
| MEJ Laser Cutting Limited | Manufacturing | 2020 |
| Meji X LEO Bespoke. Limited | Wholesale & retail | 2025 |
| Mejiro Ltd | Information & communication | 2019 |
| Mejos Properties Ltd | Real estate | 2021 |
| Mejuri (UK) Ltd. | Wholesale & retail | 2019 |
| Mekufa (UK) Limited | Manufacturing | 2002 |
| Melanie James Art Limited | Arts & recreation | 2014 |
| Melanin Records Ltd | Information & communication | 2025 |
| Melbar Limited | Hospitality | 2026 |
| Melbourne Croft Limited | Financial services | 2021 |
| Melbury Business Management Limited | Professional & scientific | 2007 |
| Melch Ltd | Professional & scientific | 2026 |
| Melchior Trading Limited | Hospitality | 2014 |
| Meldra Residents Company Limited | Households | 1989 |
| Mele Holdings Limited | Real estate | 2021 |
| Mele Town & Country Clothing Ltd | Wholesale & retail | 2012 |
| Meleke Limited | Health & social care | 2018 |
| Melfort Strategic Land Limited | Real estate | 2023 |
| Meli Poppins Childcare Limited | Health & social care | 2025 |
| Meliora & Co Building Ltd | Construction | 2025 |
| Meliora HS Ltd | Health & social care | 2025 |
| Meliorem HR Consultancy Ltd | Professional & scientific | 2017 |
| Melius Consultancy Ltd | Professional & scientific | 2010 |
| Mella Recruitment Limited | Professional & scientific | 2022 |
| Mellon Solutions Ltd | Administrative & support | 2025 |
| Mellow Financial Ltd | Financial services | 2023 |
| Mellow Moments Candles Limited | Manufacturing | 2025 |
| Mellow Services Ltd | Health & social care | 2021 |
| Melocass Limited | Real estate | 2023 |
| Melodrive Limited | Information & communication | 2022 |
| Melody - Therapy Dog Extraordinaire! Ltd | Other services | 2026 |
| Melody Bloom Ltd | Health & social care | 2024 |
| Melody Dennis Limited | Wholesale & retail | 2025 |
| Melon Head Social Ltd | Information & communication | 2024 |
| Meloria Ltd | Professional & scientific | 2022 |
| Melrose (UK) (EOT) Trustee Limited | Administrative & support | 2026 |
| Melrose (UK) Limited | Professional & scientific | 2002 |
| Melrose LAN Development Limited | Real estate | 2024 |
| Melsvie Ltd | Real estate | 2024 |
| Meltin POT Ltd | Manufacturing | 2022 |
| Melvich Wind Energy Hub Limited | Energy | 2020 |
| Melville & Melville Holdings Limited | Professional & scientific | 2021 |
| Melville Blake Ltd | Real estate | 2015 |