| Luckington Hospitality Limited | Hospitality | 2026 |
| Lucy Claire Events Limited | Administrative & support | 2016 |
| Lucy Gilchrist Marketing Limited | Other services | 2014 |
| Ludhi Trading Limited | Hospitality | 2015 |
| Ludlow Seating Services Ltd | Manufacturing | 2017 |
| Lulu’S Bumble Beez Agency Ltd | Health & social care | 2024 |
| Lumendash Ltd | Information & communication | 2022 |
| Lumley Insurance Ltd | Financial services | 1993 |
| Luna Holdings Limited | Financial services | 2016 |
| Lustra Limited | Administrative & support | 2024 |
| Luxe Cafe Bar (Cirencester) Limited | Hospitality | 2019 |
| Luxury Holiday Lodges Limited | Real estate | 2021 |
| LWI Engineering Ltd. | Professional & scientific | 2017 |
| Lyons Power Services Limited | Professional & scientific | 2018 |
| Lyra Technology Ltd | Wholesale & retail | 2024 |
| M & J Hussey Enterprises Ltd | Agriculture & fishing | 2007 |
| M & L Ellis Properties Ltd | Real estate | 2024 |
| M Baker and Sons Limited | Construction | 2003 |
| M Brunsdon Limited | Professional & scientific | 2012 |
| M F F B Academy Limited | Arts & recreation | 2015 |
| M I Electrical (Cirencester) Ltd. | Construction | 2005 |
| M Kelly Motors Ltd | Wholesale & retail | 2013 |
| M P D Contracting Limited | Professional & scientific | 2024 |
| M&M Property Services - South West Ltd | Construction | 2025 |
| Mabel Wear Ltd | Wholesale & retail | 2026 |
| MAC Pipework & Construction Ltd | Construction | 2022 |
| Machinesafe Compliance Ltd | Information & communication | 2023 |
| MAD Hatter Wine Bar Limited | Hospitality | 2016 |
| Madartwork Ltd | Professional & scientific | 2014 |
| Made by Nine Ltd. | Professional & scientific | 2013 |
| Made in Oak Limited | Extraterritorial | 2012 |
| Madsen Design Ltd | Wholesale & retail | 2011 |
| Magdalena’S General Housekeeping Services Ltd | Administrative & support | 2019 |
| Maggrow U.K. Limited | Manufacturing | 2017 |
| Magnetic Laminates Limited | Manufacturing | 2016 |
| Magnolia SPV Ltd | Construction | 2014 |
| Magor Property Investments Limited | Real estate | 2023 |
| Magpie Farm Services Ltd | Professional & scientific | 2024 |
| Maison Pro Ltd | Real estate | 2024 |
| Make a Spectacle Ltd | Wholesale & retail | 2025 |
| Make IT Home Limited | Real estate | 2017 |
| Making My Future Ltd | Extraterritorial | 2024 |
| Making Waves FX Limited | Manufacturing | 2020 |
| Malt and Anchor Limited | Extraterritorial | 2018 |
| Malvern Holyrood Tudor Estate Limited | Real estate | 2024 |
| Malvern Holyrood Tudor Management Limited | Real estate | 2024 |
| Malvern Tudor Freehold Company Limited | Real estate | 2024 |
| Malvern Tudor TEN Limited | Real estate | 2024 |
| Mana Coffee Limited | Manufacturing | 2022 |
| Manesty Consulting Limited | Hospitality | 2004 |
| Mangrove House Cirencester CIC | Hospitality | 2022 |
| Manor Court Boscombe Limited | Households | 2023 |
| Manor Farm Barns Residents Association Limited | Real estate | 1981 |
| Manor Farm Stables (Ablington) Ltd | Arts & recreation | 2013 |
| Manor Holdings Limited | Financial services | 2015 |
| Manor Home & Garden Limited | Administrative & support | 2007 |
| Maple (430) Limited | Households | 2017 |
| Maplus Agency Ltd | Health & social care | 2025 |
| Marcay Ltd | Information & communication | 2023 |
| Marches Site Investigations Ltd | Construction | 2024 |
| Margin Total Ltd | Professional & scientific | 2023 |
| Marhaba Seha Ltd | Professional & scientific | 2024 |
| Marketing Chord Ltd | Professional & scientific | 2025 |
| Marketing Data Consulting Limited | Information & communication | 2011 |
| Marlin Interiors Limited | Administrative & support | 2011 |
| Marmoset Arms Company Limited | Other services | 2014 |
| Marnhull Consulting Services Ltd | Professional & scientific | 2021 |
| Marsden Estate Partnership LLP | | 2016 |
| Marsden Sporting Limited | Arts & recreation | 2026 |
| Marston Hill Limited | Administrative & support | 2017 |
| Martin Buckley Ltd | Wholesale & retail | 2012 |
| Martin Leay Associates Limited | Professional & scientific | 2008 |
| Martin Lock Associates Limited | Professional & scientific | 1988 |
| Martin Nash Developments Limited | Construction | 2022 |
| Martin Phelps Systems Ltd | Public administration | 2005 |
| Martins & Childs Services Ltd | Agriculture & fishing | 2003 |
| Maskfit Safety Ltd | Professional & scientific | 2025 |
| Mason Farms Limited Liability Partnership | | 2009 |
| MAT Maintenance Ltd | Construction | 2019 |
| Matilda’S Bar Ltd | Hospitality | 2024 |
| Matthew Henderson Medical Limited | Health & social care | 2011 |
| Mayfield House Dynamics and Control Ltd | Professional & scientific | 2023 |
| MB Decor Ltd | Construction | 2018 |
| MBB Brasserie Limited | Hospitality | 2018 |
| MC2 Developments Ltd | Construction | 2021 |
| MCA Shepherd Smail Ltd | Professional & scientific | 2019 |
| Mcconks Ltd | Wholesale & retail | 2025 |
| Mcdonaldlawrence Limited | Arts & recreation | 2022 |
| Mcfadyen Property Development and Rentals LLP | | 2026 |
| Mcgills Limited | Professional & scientific | 2000 |
| Mcintyre Corporate Services Ltd | Professional & scientific | 2008 |
| MD Ecology Limited | Professional & scientific | 2011 |
| Measured Bras Ltd | Manufacturing | 2026 |
| Mechanical Botanical Limited | Administrative & support | 2000 |
| Media Safari Limited | Professional & scientific | 2002 |
| Medical Hardware Limited | Wholesale & retail | 2021 |
| Medicus Solutions Limited | Professional & scientific | 2026 |
| Mega Munch Tech Sales Ltd | Wholesale & retail | 2022 |
| Melanda Consulting Limited | Professional & scientific | 2012 |
| Merida Office Interiors Limited | Wholesale & retail | 2006 |