| Ladywood Residents Company Limited | Households | 1983 |
| LAG20 Consulting Limited | Professional & scientific | 2023 |
| Laguna Films Limited | Information & communication | 2010 |
| Laila and Deniz (Farnham) Ltd | Hospitality | 2021 |
| Lajna Ima'Illah (UK) | Other services | 2020 |
| Lake Resorts Ltd | Real estate | 2024 |
| Lake Therapy Ltd | Health & social care | 2018 |
| Lakeview Property (Wimbledon) Limited | Real estate | 2011 |
| Lamda Investment Group Limited | Real estate | 2023 |
| Lamelle International Limited | Wholesale & retail | 2019 |
| Lamp Cameron Holdings Limited | Financial services | 2024 |
| Lances Residents Association Company Limited | Households | 1973 |
| Landen Grove Apartments Management Company Limited | Households | 2004 |
| Landmark IT Consultants Limited | Information & communication | 2022 |
| Landmark Tree Surgery Limited | Agriculture & fishing | 2012 |
| Landpro Limited | Professional & scientific | 2002 |
| Landseer Property Limited | Real estate | 2025 |
| Landslide Productions Limited | Information & communication | 2012 |
| Langham Park Management Company Limited | Households | 2004 |
| Langley Walker LLP | | 2014 |
| Langshaw Holdings and Investments Ltd | Real estate | 2020 |
| Lansdown Place Management Limited | Households | 2025 |
| Lantern Crest Limited | Real estate | 2024 |
| Lantern Web Limited | Information & communication | 2011 |
| Lapora Estates Limited | Real estate | 2018 |
| Lapora Investments Limited | Real estate | 2015 |
| Lapora Lettings Limited | Real estate | 2021 |
| Larchbay Limited | Other services | 2014 |
| Larcher Limited | Professional & scientific | 2023 |
| Larrey Close Residents Management Company Ltd | Households | 2024 |
| Laser Lines Templating Limited | Construction | 2025 |
| Lashshack Ltd | Wholesale & retail | 2025 |
| Lasu Limited | Real estate | 2023 |
| Latchwood Holdings Ltd | Financial services | 2025 |
| Late Night Luxuries Ltd | Wholesale & retail | 2024 |
| Latimer House Freehold Company Limited | Households | 2005 |
| Latitude Sports Entertainment Ltd | Arts & recreation | 2023 |
| Latterfrosken Software Development Limited | Information & communication | 2001 |
| Laurel ARK Limited | Construction | 2024 |
| Lavastar Signs Limited | Professional & scientific | 2015 |
| Law Company (Frozen Foods) Limited | Wholesale & retail | 2002 |
| Lawnswood Investments Limited | Professional & scientific | 2020 |
| Lawrence Warren Footwear Limited | Wholesale & retail | 2013 |
| Layd Ltd | Manufacturing | 2025 |
| LB Freelance Consulting Ltd | Administrative & support | 2025 |
| LBG Underpinning Group Ltd | Construction | 2025 |
| LC Audiovisual Ltd | Extraterritorial | 2013 |
| LC Ecological Services Ltd | Administrative & support | 2002 |
| LC Moore Services Ltd | Manufacturing | 2017 |
| LC Whitworth 2 Ltd | Real estate | 2026 |
| LCD (Liquid Crystal Design) Limited | Professional & scientific | 2008 |
| Lcdtek Ltd | Wholesale & retail | 2008 |
| LCP Commercial Properties Ltd | Real estate | 2022 |
| LDX Recruitment Ltd | Administrative & support | 2019 |
| LE Page Enterprises Limited | Information & communication | 2016 |
| Lead With Sustainability Ltd | Professional & scientific | 2022 |
| Leadenhall Servicing Limited | Financial services | 2017 |
| Learnify Limited | Administrative & support | 2016 |
| Leaway Residents Company Limited | Households | 1982 |
| Ledgard Bridge Limited | Professional & scientific | 2026 |
| LEE Country Collection Ltd | Households | 2026 |
| Legend Vinyl Ltd | Manufacturing | 2020 |
| Leidar Consultancy Ltd | Information & communication | 2010 |
| Leightons Clapham Limited | Wholesale & retail | 2022 |
| Leightons Hearingcare Limited | Wholesale & retail | 2005 |
| Leightons Holdings Limited | Wholesale & retail | 1966 |
| Leightons Insight Limited | Wholesale & retail | 2013 |
| Leightons Limited | Wholesale & retail | 1943 |
| Leightons Opticians Limited | Wholesale & retail | 1952 |
| Lekke Holdings Limited | Financial services | 2023 |
| Lemon Grove Solutions Limited | Professional & scientific | 2022 |
| LEO Petroleum Ltd | Administrative & support | 2025 |
| Leo+Co Ltd | Wholesale & retail | 2020 |
| Leonard Housing (Management) Limited | Hospitality | 2005 |
| Less Blue Limited | Information & communication | 2018 |
| Lets Go Cleaning Ltd | Administrative & support | 2011 |
| Letts Save Limited | Professional & scientific | 2018 |
| Level Head Media Ltd | Information & communication | 2021 |
| Level UP Labs Limited | Information & communication | 2020 |
| Lever Movement Limited | Information & communication | 2025 |
| Leveredge Ltd | Administrative & support | 2025 |
| Levern Drive Limited | Households | 1984 |
| Levy Building Contractors Ltd. | Construction | 2017 |
| Lewington Homes Limited | Construction | 2004 |
| LEX and LOE Creative Ltd | Professional & scientific | 2024 |
| Leyth Hampshire Ltd | Other services | 2023 |
| LF Construction Group Limited | Construction | 2025 |
| LG Building and Roofing Ltd | Construction | 2022 |
| Lgwo Holdings Limited | Financial services | 2023 |
| LH Creative Graphics Ltd | Professional & scientific | 2022 |
| Liberate Estimating Limited | Information & communication | 2015 |
| Liberty Charters Estates Ltd | Real estate | 2019 |
| Lida Logistics Limited | Transport & logistics | 2021 |
| Lidan Group Limited | Financial services | 2023 |
| Lifespeed Ltd | Wholesale & retail | 2023 |
| Lifestyle Fitness Formula Ltd | Other services | 2025 |
| Lifestyle Planning Limited | Professional & scientific | 2016 |
| Lift & Shoot Limited | Extraterritorial | 2001 |
| Liftkeeper Limited | Information & communication | 2021 |
| Light Blue Horizon Ltd | Information & communication | 2019 |