| LCA Heating Ltd | Construction | 2023 |
| LE Adler Limited | Professional & scientific | 2021 |
| Lear Rifles Limited | Manufacturing | 2022 |
| LEARNER2MENTOR Limited | Education | 2009 |
| Learningandleadership Limited | Administrative & support | 2019 |
| Learnium Academy Ltd | Education | 2026 |
| Legacy LDN Beauty Ltd | Other services | 2020 |
| Legacy Locs Ltd | Other services | 2026 |
| Legend Kebab YK Limited | Hospitality | 2025 |
| Legume Delicia Ltd | Hospitality | 2019 |
| Leigh DB (JMD) Ltd | Construction | 2021 |
| Leigham Road Limited | Real estate | 2025 |
| Leisure & Adventure Limited | Extraterritorial | 2025 |
| Lemcare Limited | Administrative & support | 2024 |
| Lenio Business Services Limited | Professional & scientific | 2004 |
| Lenvic Crochet Ltd | Wholesale & retail | 2024 |
| Leon Berry Services Ltd | Information & communication | 2016 |
| Leon Horticultural Design and Maintenance Limited | Administrative & support | 2018 |
| Leon Krykhtin Design Network Ltd | Professional & scientific | 2021 |
| Leona Brown Limited | Health & social care | 2024 |
| Leonard Leigh Limited | Transport & logistics | 2009 |
| Leonora Limited | Health & social care | 2013 |
| Lesther Properties Ltd | Real estate | 2025 |
| LEX Graeca Limited | Professional & scientific | 2020 |
| Lexridge Limited | Professional & scientific | 2025 |
| LFS Wealth Limited | Financial services | 2026 |
| LG Kebab Centre Ltd | Hospitality | 2025 |
| LGM Removals Limited | Transport & logistics | 2020 |
| Liebling Limited | Information & communication | 2010 |
| Lifeoffocus Ltd | Other services | 2023 |
| Lifespan Solutions Limited | Health & social care | 2018 |
| Lift Coffee Limited | Wholesale & retail | 2018 |
| Lightwood Court Company Limited | Households | 1995 |
| Lily's Property Ltd | Real estate | 2024 |
| Lindrea Services Ltd | Arts & recreation | 2020 |
| Lines Accounting Ltd | Professional & scientific | 2003 |
| Lingpoint Consulting Ltd | Professional & scientific | 2025 |
| Lion's Cleaning Service Limited | Administrative & support | 2017 |
| Lionsong Limited | Information & communication | 2015 |
| Liquid Assets (2015) Ltd | Real estate | 2015 |
| Liquid Assets 2011 Limited | Real estate | 2011 |
| Liquid Assets 2011 SPV Limited | Real estate | 2018 |
| Lisle Services Limited | Construction | 2018 |
| Little Apples Day Nursery Ltd | Education | 2011 |
| Little YII Ltd | Wholesale & retail | 2025 |
| Livecare Ltd | Health & social care | 2020 |
| Livenza Housing Ltd | Real estate | 2025 |
| LJ Hugs Limited | Hospitality | 2014 |
| LJH Veterinary Consultancy Ltd | Professional & scientific | 2014 |
| Lloyds Security Services Limited | Administrative & support | 2006 |
| LLY Accountancy Ltd | Professional & scientific | 2020 |
| Lmdec Ltd | Construction | 2018 |
| LN Essence Ltd | Wholesale & retail | 2025 |
| Lobster Construction Management Limited | Professional & scientific | 2009 |
| Local Art Print Ltd | Arts & recreation | 2026 |
| Local Hardware Ltd | Wholesale & retail | 2024 |
| Local Traders Ltd | Wholesale & retail | 2025 |
| Loda World Ltd | Wholesale & retail | 2018 |
| Lodge Music Limited | Arts & recreation | 2006 |
| Loft Haven Ltd | Construction | 2025 |
| Log-On Technology Limited | Real estate | 2016 |
| Logidal Group Limited | Wholesale & retail | 2021 |
| Lognix Ltd | Wholesale & retail | 2026 |
| LOI & GEO Properties Limited | Real estate | 2014 |
| Lois Elizabeth Limited | Other services | 2023 |
| Lola GM Limited | Information & communication | 2016 |
| London Academy of Freelance Makeup Ltd | Education | 2006 |
| London Airport Transfers MPV Ltd | Other services | 2012 |
| London and Surrey Mouldings Limited | Construction | 2014 |
| London Breast Imaging Limited | Professional & scientific | 2016 |
| London Capital & Investment Limited | Other services | 2019 |
| London Dreams Construction Ltd | Construction | 2024 |
| London General Media Ltd | Professional & scientific | 2023 |
| London Housekeeping Limited | Administrative & support | 2026 |
| London Luxury Interiors Ltd | Construction | 2024 |
| London Manchester Properties Limited | Real estate | 2003 |
| London Needs Cooling Limited | Construction | 2000 |
| London Proinvest Ltd | Real estate | 2017 |
| London Russell Education Ltd. | Information & communication | 2014 |
| London Wheelchair Hire Ltd | Administrative & support | 2017 |
| London Young Diabetes Limited | Health & social care | 2016 |
| Londonmedicaldoctors Ltd | Health & social care | 2020 |
| Londonpcfix Ltd | Wholesale & retail | 2021 |
| Long Story Short Productions Ltd | Information & communication | 2020 |
| Longmead 1960 Limited | Extraterritorial | 2014 |
| Look Red Limited | Information & communication | 1987 |
| Looking Glass Management Ltd | Professional & scientific | 2024 |
| Loop Games UK Ltd | Financial services | 2021 |
| Lopost Limited | Transport & logistics | 2023 |
| Loqum Restaurant Limited | Hospitality | 2017 |
| LOS Amigos Cafe & Sandwich Bar Limited | Hospitality | 2017 |
| Love, Dating & Marriage Ltd | Other services | 2022 |
| Loveday and Associates Limited | Professional & scientific | 2021 |
| LS UK Enterprise Ltd | Other services | 2020 |
| LSO Consulting Limited | Professional & scientific | 2019 |
| LT Environmental Limited | Professional & scientific | 2009 |
| Ltd Accountancy Ltd | Professional & scientific | 2011 |
| Lucid Consulting (TW) Ltd. | Professional & scientific | 2006 |
| Lucitrans Ltd | Transport & logistics | 2022 |
| Ludgate Lunch Box Limited | Hospitality | 2024 |