| Lemon Zest Cuisine Limited | Hospitality | 2001 |
| Leonfamprop Ltd | Real estate | 2024 |
| Letzpool Ltd | Information & communication | 2026 |
| Levaracollective Ltd | Wholesale & retail | 2026 |
| Lewis Baldwin Fitness & Coaching Ltd | Arts & recreation | 2023 |
| Libertine Spirits Ltd | Wholesale & retail | 2009 |
| Lifepaths Partnership Limited | Health & social care | 2004 |
| Lime Green Exhibitions Limited | Manufacturing | 2015 |
| Liquats UK Ltd | Manufacturing | 2024 |
| Litelead Ltd | Transport & logistics | 2021 |
| Little Hoofprints Ltd | Education | 2021 |
| Little Light PR Limited | Professional & scientific | 2019 |
| Little Purston Farm Limited | Hospitality | 2023 |
| Live Love BE Limited | Health & social care | 2016 |
| Lively Catering Limited | Hospitality | 2025 |
| Livemix Production Services Limited | Arts & recreation | 2005 |
| Living Homestyles Ltd | Construction | 2016 |
| Lizst Price Accountants Limited | Professional & scientific | 2023 |
| Lizst Price Accounting Limited | Professional & scientific | 2007 |
| Lizst Price Limited | Professional & scientific | 2002 |
| LLJ Trading Limited | Construction | 2018 |
| Lodestone Search Limited | Administrative & support | 2020 |
| Logistics Engineering Design Ltd | Professional & scientific | 2016 |
| Long Property Services Limited | Financial services | 2017 |
| Longwood Enterprises Limited | Real estate | 2012 |
| Lormay Management Limited | Households | 2015 |
| Lottie Elizabeth Ltd | Manufacturing | 2022 |
| Lourdes Takeaway Limited | Hospitality | 2024 |
| Lovell Plumbing & Heating Ltd | Construction | 2024 |
| Lovetone FX Ltd | Manufacturing | 2026 |
| LOW Dempsey Racing Limited | Arts & recreation | 2019 |
| Lucas Enterprises Limited | Hospitality | 2007 |
| Lucie App Ltd | Information & communication | 2022 |
| Lucy Russell Limited | Professional & scientific | 2010 |
| Luke Gibbard Sports Therapy Limited | Health & social care | 2017 |
| M & J Haynes Properties Limited | Real estate | 2024 |
| M E Paxton Limited | Manufacturing | 2012 |
| M Faria Consultants Limited | Professional & scientific | 2017 |
| M G Health & Safety (UK) Limited | Professional & scientific | 2010 |
| M&C Property ( York ) Ltd | Real estate | 2021 |
| M. Page Building Services Limited | Construction | 2013 |
| M. Page Developments Limited | Construction | 2011 |
| M.G.Walker Recovery Ltd | Wholesale & retail | 2018 |
| M.K.T. Computer Brokers Limited | Wholesale & retail | 1999 |
| MA Refractory Inspections Ltd | Professional & scientific | 2012 |
| MAB Ventures Limited | Professional & scientific | 2014 |
| Macjeannes Limited | Administrative & support | 2003 |
| Macvander Ltd | Professional & scientific | 2011 |
| Maday Racing Ltd | Wholesale & retail | 2022 |
| Made With Integrity Limited | Wholesale & retail | 2026 |
| MAG Management Services Limited | Professional & scientific | 2020 |
| Magdalen College School Brackley Academy Trust | Education | 2012 |
| Magic Hour Creatives Ltd | Professional & scientific | 2023 |
| Magnum RPS Limited | Administrative & support | 2025 |
| Maguire Property Investments Limited | Real estate | 2018 |
| Maidaid Limited | Administrative & support | 1998 |
| Mango 8 Ltd | Wholesale & retail | 2025 |
| Mango Communications Ltd | Information & communication | 2015 |
| Mansfield Farm Estates Limited | Real estate | 2013 |
| Mansfield Technical Consultants Limited | Professional & scientific | 2024 |
| Mansfield-Painting Master Thatchers Limited | Construction | 2024 |
| Mantica Ltd | Professional & scientific | 2025 |
| Mapleleaf Building Services Ltd | Construction | 2020 |
| March Cleaning Services Limited | Administrative & support | 2007 |
| Marcus James Property Ltd | Real estate | 2022 |
| Mark Thomas Design Ltd | Professional & scientific | 2015 |
| Marksman Events Ltd | Arts & recreation | 2024 |
| Martin Drew Property Agent Ltd | Real estate | 2023 |
| Massoss Limited | Wholesale & retail | 2008 |
| Matchmytrainer Limited | Information & communication | 2026 |
| Matrix Logic Limited | Information & communication | 1978 |
| Matt Cowing Limited | Professional & scientific | 2003 |
| Mavin Holdings Ltd | Financial services | 2022 |
| Maxime Solutions Limited | Wholesale & retail | 2013 |
| Maximum Exhibitions Limited | Administrative & support | 2023 |
| MAY Moments Ltd | Administrative & support | 2025 |
| Mayfield Motor Sports Limited | Arts & recreation | 2017 |
| Mayfield Realty Limited | Real estate | 2016 |
| Mayfield Sports Events Limited | Arts & recreation | 2025 |
| Mayhemhouse Limited | Information & communication | 2020 |
| MB Services Ventures (Midlands) Limited | Real estate | 2018 |
| MC Cabinets Limited | Manufacturing | 2017 |
| Mccann Family LLP | | 2006 |
| Mccann Investment Property LLP | | 2015 |
| Mccann Property Partners Limited | Real estate | 2026 |
| Mccobb Consulting Limited | Professional & scientific | 2008 |
| Mcmillan Maclean Limited | Professional & scientific | 2017 |
| MDA Installations Limited | Manufacturing | 2007 |
| MDB Wills Ltd | Professional & scientific | 2025 |
| Meckland Ltd | Real estate | 1997 |
| Medicine Horse Limited | Professional & scientific | 2015 |
| Meister Continental Foods Limited | Manufacturing | 1977 |
| Melanie Jayne Soft Furnishings Ltd | Manufacturing | 2022 |
| Mellow Meats Ltd | Agriculture & fishing | 2020 |
| Mercedes-Benz Grand Prix Ltd | Arts & recreation | 1964 |
| Mercedes-Benz Motorsport Limited | Administrative & support | 2020 |
| Meti Health Ltd | Professional & scientific | 2024 |
| Mezurashi Limited | Professional & scientific | 2023 |
| Mhkh Consulting Limited | Agriculture & fishing | 2014 |
| MI Eco Consulting Ltd | Wholesale & retail | 2022 |