| Ljbouchard Consultancy Ltd | Information & communication | 2023 |
| LL Financial Services Ltd | Professional & scientific | 2015 |
| LLH Interim Management Services Limited | Hospitality | 2002 |
| Lmirific Consultancy Ltd | Information & communication | 2024 |
| Location Remedy Ltd | Administrative & support | 2021 |
| Loddon Healthcare Ltd | Health & social care | 2022 |
| Logic Contract Services Ltd | Construction | 2016 |
| Logik Electrical Limited | Construction | 2005 |
| Loissky Property Investment Limited | Real estate | 2025 |
| Lomashome Property Management Limited | Hospitality | 1996 |
| Loming AI Limited | Information & communication | 2023 |
| London Ride & Tour Limited | Transport & logistics | 2025 |
| Lorry Legend Ltd | Transport & logistics | 2025 |
| Loud Mouth Music Group Ltd | Information & communication | 2022 |
| Louise Barnett Public Relations Limited | Professional & scientific | 2009 |
| Louw Capital Ltd | Professional & scientific | 2021 |
| Love Cleaning London Ltd | Administrative & support | 2021 |
| LPG Sussex Ltd | Financial services | 2024 |
| LR6 Academy Ltd | Arts & recreation | 2024 |
| LS Home Properties Limited | Households | 2026 |
| Lucinda Green XC Academy Ltd | Other services | 2020 |
| Lucky 4 S Ltd | Real estate | 2024 |
| Lucy Xfit Ltd | Arts & recreation | 2023 |
| Luna Creative Limited | Professional & scientific | 2014 |
| Luna Group East Sussex Ltd | Construction | 2018 |
| Luna Group Estates Ltd | Households | 2017 |
| Luna Group GM Ltd | Construction | 2018 |
| Luna Group LH Limited | Real estate | 2018 |
| Luna Group MH Limited | Real estate | 2018 |
| Lunar Prop Ltd | Real estate | 2026 |
| Lusufalia Limited | Wholesale & retail | 2024 |
| Luxehouse Decor Ltd | Manufacturing | 2025 |
| Luxhomes Properties Ltd | Households | 2026 |
| LYC Limited | Financial services | 2026 |
| Lymington (Bridge Road) Management Company Limited | Households | 2008 |
| Lymington Prospect Builders Ltd | Construction | 1982 |
| Lynx (JB) Holdings Ltd | Financial services | 2024 |
| Lynx Forecourt Limited | Construction | 2001 |
| Lynx Infotech Ltd | Information & communication | 2014 |
| Lynx Lettings Limited | Real estate | 2011 |
| Lyonesse PZ81 Limited | Manufacturing | 2018 |
| M and L Pet Care Ltd | Other services | 2009 |
| M Ewas Limited | Professional & scientific | 2014 |
| M H Animal Foods Limited | Wholesale & retail | 2006 |
| M&B Business Solutions Ltd | Administrative & support | 2019 |
| M&C International Ltd | Wholesale & retail | 2020 |
| M&J Prop Ltd | Real estate | 2024 |
| M&K Mart Ltd | Wholesale & retail | 2022 |
| M&L Body Refinishers Ltd | Wholesale & retail | 2025 |
| M.E. Foxwell Roofing Services Ltd | Construction | 2026 |
| M3 Heating and Plumbing Limited | Construction | 2022 |
| M3 Roofing Ltd | Construction | 2026 |
| Maccoonalo Ltd | Information & communication | 2018 |
| Machine Learning Droids Ltd | Information & communication | 2021 |
| Mackencore UK Limited | Manufacturing | 2019 |
| Mackenzie Smith Properties Limited | Real estate | 1993 |
| Mackenzie Smith Property Lettings & Management Limited | Households | 2013 |
| MAD Eddie's Limited | Professional & scientific | 2016 |
| MAD OX Brewery Limited | Extraterritorial | 2021 |
| Made to Measure Travel Ltd | Administrative & support | 2024 |
| Magcirc Solutions Ltd | Administrative & support | 2025 |
| Magellan Consultants Limited | Professional & scientific | 2013 |
| MAI Tech Limited | Information & communication | 2017 |
| Maillot Jaune Communications Limited | Professional & scientific | 2005 |
| Maine Capital Management Limited | Real estate | 2017 |
| Make a Scene Studio Ltd | Administrative & support | 2022 |
| Malingo Aldershot Ltd | Hospitality | 2018 |
| Management and Contract Services Ltd | Extraterritorial | 2010 |
| Mandiki Limited | Professional & scientific | 2018 |
| Mandiki Property Limited | Real estate | 2022 |
| Maneetapho Housing Limited | Construction | 2021 |
| Manent Ltd | Administrative & support | 2023 |
| Manjo Holdings Ltd | Real estate | 2019 |
| Manor Court (Sandy Lane) Limited | Households | 2016 |
| Manor Court (Sandy Lane) Management Limited | Real estate | 1989 |
| Manor Rise Block C Management Company Limited | Households | 2023 |
| Manor View (East Grinstead) Residents Management Company Limited | Households | 2021 |
| MAR Creative Limited | Professional & scientific | 2019 |
| Marbley Limited | Wholesale & retail | 2022 |
| Maritime Limits and Boundaries Services Limited | Professional & scientific | 2010 |
| Mark a B Travel Ltd | Administrative & support | 2026 |
| Markham House (Farnborough) RTM Company Ltd | Households | 2017 |
| Marrus Projects Ltd | Construction | 2020 |
| Mass Fire Protection Ltd | Construction | 2023 |
| Mastrad Properties Limited | Real estate | 2002 |
| Matrix Travel Limited | Wholesale & retail | 2025 |
| Matthew Hamilton Ltd | Professional & scientific | 2015 |
| Maxline Agencies Ltd | Professional & scientific | 2002 |
| Mayfair Court RTM Company Ltd | Households | 2008 |
| Maynelines Blinds Limited | Wholesale & retail | 2011 |
| MC Wise Property Limited | Real estate | 2020 |
| Mccalla Events Limited | Hospitality | 2025 |
| Mccance Construction Ltd | Construction | 2013 |
| Mccreath Consulting Ltd | Administrative & support | 2019 |
| Mcculloch CAD Services Ltd | Administrative & support | 2005 |
| Mcculloch Property Ltd | Real estate | 2019 |
| Mcsharry Ltd | Financial services | 2026 |
| Mcwilliam Finance Limited | Professional & scientific | 2023 |
| MD Asbestos Solutions Ltd | Water & waste | 2020 |
| MDB Partners Limited | Manufacturing | 2005 |