| LAS Equipment Ltd | Mining & quarrying | 2019 |
| LAS Groupe Ltd | Extraterritorial | 2021 |
| Lash Luscious Aesthetics Limited | Other services | 2023 |
| Lash Luscious Beauty Academy Limited | Education | 2024 |
| Lash Luscious Limited | Other services | 2020 |
| Lauren Evans Casting Ltd | Administrative & support | 2020 |
| Lavyxco Ltd | Wholesale & retail | 2026 |
| Layla LEY Ltd | Arts & recreation | 2026 |
| LB3 Construction Limited | Construction | 2026 |
| Leafield Equestrian Limited | Agriculture & fishing | 2016 |
| LED Lights Pro Ltd | Wholesale & retail | 2024 |
| LEE Smith's Scrap Metals Limited | Water & waste | 2013 |
| Leedhome Limited | Real estate | 1996 |
| Legacy Global 22 Limited | Wholesale & retail | 2022 |
| Leigh Cantero Services Ltd | Professional & scientific | 2025 |
| Lemke ENG Limited | Information & communication | 2011 |
| Let's BE Connected Ltd | Information & communication | 2024 |
| Lever Properties Limited | Real estate | 2002 |
| Lewis 11 Holdings Limited | Financial services | 2023 |
| Lexham Insurance Consultants Limited | Financial services | 1999 |
| LHC Projects Ltd | Construction | 2025 |
| LHS Locks & Home Security Ltd | Administrative & support | 2000 |
| Life Matters Centre Limited | Other services | 2011 |
| Lime Tree Cattery Limited | Other services | 2023 |
| Limitless Design and Print Ltd | Information & communication | 2023 |
| Limitless Futures CIC | Education | 2023 |
| Lion Tyres (Essex) Ltd | Wholesale & retail | 2023 |
| Little Chippy Ltd | Hospitality | 2017 |
| Little Ouse Headwaters Project | Arts & recreation | 2003 |
| LJG Associates Limited | Real estate | 2014 |
| LJP Contracting Limited | Manufacturing | 2025 |
| Ljtransport Ltd | Transport & logistics | 2022 |
| Loddon Nursery School Limited | Education | 2016 |
| Loke Cottages Limited | Real estate | 2026 |
| Long Stratton Pigs Limited | Agriculture & fishing | 2017 |
| Lopham Vehicle Services Ltd | Wholesale & retail | 2015 |
| Louies Court Freeholders Limited | Administrative & support | 2019 |
| Love Rituals Ltd | Other services | 2025 |
| Lower Lodge Productions Limited | Arts & recreation | 1990 |
| Loxton Construction Limited | Construction | 2023 |
| LP Property Developments Ltd | Construction | 2023 |
| LR Entertainment Ltd | Information & communication | 2019 |
| Lunarplace Limited | Real estate | 1985 |
| LXM Management Limited | Financial services | 2003 |
| Lysander R&D Limited | Professional & scientific | 2012 |
| M Cullum Haulage Ltd | Transport & logistics | 2026 |
| M J Garrod and Sons Ltd | Agriculture & fishing | 2012 |
| M&T Global Ltd | Professional & scientific | 2024 |
| M.B. Electrical (Lakenheath) Limited | Construction | 2002 |
| M.C Trans Universal Limited | Other services | 2015 |
| M.G. Fitness Ltd. | Education | 2008 |
| M.Minns Limited | Real estate | 2025 |
| M.T. Aves and Sons Limited | Agriculture & fishing | 2006 |
| MA Marketing and Consultancy Ltd | Professional & scientific | 2022 |
| Mabalex Ltd | Transport & logistics | 2026 |
| MAD Marvel Media Ltd | Information & communication | 2026 |
| Madgett's Cycles Limited | Manufacturing | 2007 |
| Magdalen Street Development Limited | Construction | 2018 |
| Magnolia Mortgages Ltd | Financial services | 2021 |
| Malcolm Kidd Car & Commercial Ltd | Wholesale & retail | 2026 |
| MALIH01 Limited | Hospitality | 2026 |
| Malthouse (Ludham) Limited | Real estate | 1973 |
| Malyon Consulting Limited | Professional & scientific | 2002 |
| Mamco IT Ltd | Information & communication | 2019 |
| Manor House Oak Ltd | Construction | 2022 |
| Mapex Electrical Ltd | Construction | 2025 |
| Maple Carpentry & Building Ltd | Construction | 2021 |
| Marble Arch Claims Services Ltd | Financial services | 2018 |
| Marble Arch Insurance Ltd | Extraterritorial | 2017 |
| Marble Arch Underwriting Ltd | Extraterritorial | 2017 |
| Mardave Limited | Manufacturing | 2010 |
| Market Hill Hair Ltd | Other services | 2002 |
| Marsh Agricultural Cleaning Services Ltd | Agriculture & fishing | 2019 |
| Marsh Architects Limited | Professional & scientific | 2022 |
| Marshall Haulage Limited | Transport & logistics | 2018 |
| Martin Marinov Vending Ltd | Hospitality | 2021 |
| Martin Scowcroft Wealth Management Limited | Professional & scientific | 2017 |
| Martin Travel Limited | Administrative & support | 2021 |
| Marvellous History Ltd | Education | 2019 |
| Masefield Veterinary Services Ltd | Professional & scientific | 2008 |
| Mashmonkey Craft Brewery Ltd | Manufacturing | 2025 |
| Maskrey Thompson Ltd | Other services | 2005 |
| Master Control Construction Ltd | Construction | 2024 |
| MAV Group Holdings Ltd | Financial services | 2025 |
| MAV Hire Ltd | Administrative & support | 2025 |
| MAX Dixon Surveying Ltd | Professional & scientific | 2023 |
| Mckeown & Co Ltd | Wholesale & retail | 2015 |
| MCN SUB Limited | Extraterritorial | 2024 |
| MDB Freight Solutions Ltd | Transport & logistics | 2018 |
| Measures Consulting Limited | Professional & scientific | 2010 |
| Mechtroniks Limited | Manufacturing | 2018 |
| Mecklermedical Limited | Extraterritorial | 2020 |
| Med&Vet UK Ltd | Wholesale & retail | 2004 |
| Meditransport Ambulance Supply & Funding Limited | Health & social care | 2015 |
| Mendlesham Homes Ltd | Construction | 2007 |
| Mereside Mews Management Company Limited | Professional & scientific | 2017 |
| Merit Plastic Holdings Limited | Financial services | 1978 |
| Merit Plastic Mouldings Limited | Manufacturing | 1973 |
| Merit Plastics Limited | Financial services | 1980 |
| Merrells Properties Ltd | Construction | 2019 |