| Lighthouse Support Solutions Ltd | Administrative & support | 2024 |
| Lika 28 Limited | Construction | 2016 |
| Lilingbale Consultancy UK Limited | Education | 2017 |
| Lime Chai Ltd | Hospitality | 2022 |
| Limewood Money Ltd | Financial services | 2022 |
| Linden Steele Ltd | Financial services | 2023 |
| Linea Analytics Ltd | Administrative & support | 2025 |
| Link Bridge Ltd | Professional & scientific | 2023 |
| Link ZEN Ltd | Wholesale & retail | 2011 |
| Lise Lous Ltd | Hospitality | 2022 |
| LITEW8 Ltd | Information & communication | 2025 |
| Litmus Consulting Limited | Information & communication | 2016 |
| Litmus Developments Limited | Information & communication | 2018 |
| Little Tarpots Court RTM Company Limited | Real estate | 2015 |
| Little Wycke Liveries Ltd | Agriculture & fishing | 2011 |
| LIV Global Travel Ltd | Administrative & support | 2025 |
| Live Horizon Limited | Other services | 2007 |
| Live Laugh Smile Ltd | Health & social care | 2024 |
| Livermore Plant Hire Ltd | Construction | 2023 |
| Livetel Solutions Limited | Information & communication | 2012 |
| Living Bread Christian Ministries International Limited | Other services | 2024 |
| Living Life Supported Living Ltd | Health & social care | 2025 |
| Livwell Health & Fitness Limited | Arts & recreation | 2024 |
| LJA Surveyors Ltd | Professional & scientific | 2024 |
| LJF Basements and Substructures Limited | Construction | 2003 |
| LJM Connect Ltd | Professional & scientific | 2026 |
| Lloyds (Mastics) Limited | Construction | 1980 |
| LO Roche Bureau Ltd | Professional & scientific | 2025 |
| LO Roche Business Services Limited | Professional & scientific | 2011 |
| Loah Cars & Recovery Limited | Wholesale & retail | 2021 |
| Local Pest Control Services Ltd | Professional & scientific | 2022 |
| Location Surveys Ltd | Professional & scientific | 2015 |
| Lodge Liveries Ltd | Administrative & support | 2009 |
| Logic Air Limited | Energy | 2020 |
| Logic Fire Solutions Limited | Construction | 2020 |
| London & Essex Pest Control Ltd | Administrative & support | 2025 |
| London and County Investments Limited | Real estate | 2015 |
| London and South East Valuers Ltd | Professional & scientific | 2020 |
| London Aquarium Maintenance Ltd | Professional & scientific | 2009 |
| London Aquariums Ltd | Wholesale & retail | 2013 |
| London Asbestos Ltd | Construction | 2023 |
| London Asbestos Removals Limited | Professional & scientific | 2016 |
| London Asbestos Surveys Ltd | Professional & scientific | 2016 |
| London Bailiff Services Ltd | Professional & scientific | 2024 |
| London Bars Ltd | Hospitality | 2004 |
| London Gaming BUS Limited | Arts & recreation | 2022 |
| London Industrial Fabrication Company Limited | Professional & scientific | 1979 |
| London Tenant Evictions Ltd | Professional & scientific | 2024 |
| Long Construction Limited | Construction | 2024 |
| Longbridge Lettings & Property Services Limited | Other services | 2010 |
| Longlade Property Rentals Ltd | Real estate | 2018 |
| Longstomps Ltd | Other services | 2021 |
| Look Aesthetics Ltd | Other services | 2020 |
| Lormar Rail Ltd | Construction | 2017 |
| Lorraine Consulting Limited | Health & social care | 2015 |
| Love HR Consultancy Ltd | Administrative & support | 2023 |
| Love Luck Productions Ltd | Information & communication | 2022 |
| Loveday’S Landscaping Ltd | Administrative & support | 2023 |
| Lovelace Avenue Management Ltd | Households | 2011 |
| Lowermain Limited | Real estate | 1986 |
| Loxy World Ltd | Wholesale & retail | 2025 |
| LP Draughting Services Ltd | Professional & scientific | 2021 |
| LPV Ltd | Hospitality | 2024 |
| LRB Electrical & Building Solutions Limited | Construction | 2018 |
| LRD Construction Services Limited | Construction | 2011 |
| Lrtof Limited | Other services | 2020 |
| LSA Executive Transport Ltd | Transport & logistics | 2022 |
| LSH Estates Ltd | Real estate | 2025 |
| LSJ Safety Limited | Public administration | 2020 |
| LSV Reedham Ltd | Construction | 2025 |
| LSV ST Mary's Ltd | Construction | 2025 |
| LT Film Solutions Ltd | Information & communication | 2012 |
| LTA Consulting Ltd | Construction | 2025 |
| Lucy Watts Ltd | Health & social care | 2018 |
| Luke & Co Creative Ltd | Professional & scientific | 2013 |
| Luke Bathrooms & Kitchens Ltd | Construction | 2016 |
| Lumora AI Ltd | Information & communication | 2025 |
| Luna Executive Consulting Ltd | Professional & scientific | 2021 |
| Lush by Lottie Ltd | Other services | 2024 |
| Luxury Maintenance Services Ltd. | Construction | 2017 |
| LW Measurements Europe Limited | Wholesale & retail | 2012 |
| Lyla Lupa Ltd | Wholesale & retail | 2024 |
| Lynton Gate Management Company Limited | Households | 2017 |
| M & G Southern (UK) Ltd | Construction | 2019 |
| M & J Associates Limited | Professional & scientific | 2017 |
| M & J Yeldham Ltd | Construction | 2015 |
| M & L Painting & Decorating Limited | Construction | 2022 |
| M & S Cormack Limited | Manufacturing | 2002 |
| M C Interior Solutions Ltd | Manufacturing | 2014 |
| M D Flack Building Services Ltd | Construction | 2026 |
| M G & a Engineering Limited | Manufacturing | 2003 |
| M Goodbourn Ltd | Information & communication | 2023 |
| M I Fire Protection Limited | Construction | 2014 |
| M K Dhuna Limited | Health & social care | 2008 |
| M Mikita Ltd | Administrative & support | 2020 |
| M P Cabling Limited | Information & communication | 2005 |
| M P Decorating & Design Ltd | Construction | 2018 |
| M S Westons Limited | Construction | 2022 |
| M&Csidey Property Ltd | Real estate | 2025 |
| M&N Dental Limited | Health & social care | 2023 |