| Kris Handyman Limited | Administrative & support | 2017 |
| Krishnadev Limited | Health & social care | 2021 |
| Krisnar Limited | Real estate | 2021 |
| Kristeak Ltd | Wholesale & retail | 2026 |
| KRK Limited | Construction | 2013 |
| Krombacher Drinks UK Limited | Other services | 2014 |
| KSB Developments Limited | Real estate | 2020 |
| KSB Estates Limited | Financial services | 2020 |
| KSB Urban Homes Limited | Real estate | 2020 |
| Ksri Ltd | Wholesale & retail | 2016 |
| Ktanwa Limited | Real estate | 2026 |
| Kubera Investments Ltd | Real estate | 2020 |
| Kula Investments Ltd | Real estate | 2022 |
| Kulinska Ltd | Professional & scientific | 2025 |
| Kumaran UK Limited | Real estate | 2003 |
| Kuzafin Ltd | Administrative & support | 2025 |
| KV Air Conditioning Services Ltd | Extraterritorial | 2024 |
| Kvrk Limited | Construction | 2026 |
| Kytec Limited | Professional & scientific | 1995 |
| L. C. Newton Limited | Wholesale & retail | 1997 |
| L.Gabriel Engineering Limited | Professional & scientific | 2018 |
| L2O Coaching Ltd | Professional & scientific | 2022 |
| Laburnum House Management Limited | Households | 1984 |
| Laleham LEA School | Education | 2007 |
| Lalm Futūrus Services Ltd | Health & social care | 2025 |
| Lamb Home Inspectors Limited | Other services | 2007 |
| Land ARK Limited | Real estate | 2025 |
| Landhi Ltd | Professional & scientific | 2022 |
| Larry Junior Okuleye Ltd | Transport & logistics | 2021 |
| Lavita Velo Ltd | Wholesale & retail | 2021 |
| Lawnstar Limited | Other services | 2006 |
| LBM 2022 Ltd | Other services | 2018 |
| LCM Fortune Limited | Wholesale & retail | 2024 |
| Leadadvisor Ltd | Professional & scientific | 2025 |
| Lean Scrum Global Ltd | Information & communication | 2021 |
| Learn With FLO Ltd | Extraterritorial | 2024 |
| LEE Homes & Investments Ltd | Real estate | 2025 |
| Leederajan Holdings Ltd | Real estate | 2015 |
| Leena Patel Legacy Productions Ltd | Arts & recreation | 2016 |
| Leescrowncouture Ltd | Other services | 2026 |
| Legal AID Consultants Ltd | Professional & scientific | 2013 |
| Lemon Logic Limited | Information & communication | 2002 |
| Lemonwedge Collective CIC | Information & communication | 2025 |
| Lemonwedge Film Club Ltd | Information & communication | 2018 |
| Lemonwedge Productions Ltd | Administrative & support | 2010 |
| LEO Driving School Ltd | Education | 2025 |
| Lesko Installations Ltd | Construction | 2025 |
| LET HIM Cook Limited | Wholesale & retail | 2025 |
| Levbrook Professional Services Limited | Professional & scientific | 1996 |
| Leverage Worldwide Group Ltd | Wholesale & retail | 2003 |
| LEX Sterling Limited | Other services | 2015 |
| LFR Consulting Limited | Professional & scientific | 2026 |
| Lhsa Ltd | Hospitality | 2025 |
| Libre Estates Ltd | Hospitality | 2024 |
| Lina&Theou Ltd | Wholesale & retail | 2022 |
| Link Hospitality Limited | Hospitality | 2025 |
| Linklane Education Ltd | Education | 2011 |
| Linksfield Nominees Limited | Professional & scientific | 2011 |
| Liqui Moly UK Limited | Other services | 2021 |
| Lister Court Freeholders Limited | Real estate | 1997 |
| Little Bunnies Childcare Limited | Health & social care | 2014 |
| Little Foxley's Management Company Limited | Households | 2000 |
| Little Kittens Childcare Limited | Health & social care | 2017 |
| Little London Concierge Ltd | Administrative & support | 2024 |
| Little Sneakers Childcare Limited | Health & social care | 2015 |
| LMK Consulting Ltd | Professional & scientific | 2025 |
| LMK Trading Limited | Real estate | 2023 |
| Locations Management Ltd | Households | 2019 |
| Locks of London Limited | Professional & scientific | 2003 |
| Lockstock Fire Security Limited | Administrative & support | 1990 |
| Lockstock Security Limited | Administrative & support | 2013 |
| Lodgical Accounts Limited | Professional & scientific | 2014 |
| Logic Works IT Solutions Limited | Information & communication | 2026 |
| London Book Exports Ltd | Wholesale & retail | 2021 |
| London Devices Ltd | Professional & scientific | 2023 |
| London Lash Limited | Other services | 2026 |
| London Study Campus International Ltd | Education | 2025 |
| Looked After CIC | Administrative & support | 2026 |
| Lounge Hire Events Ltd | Hospitality | 2023 |
| Love Electrics Services Ltd | Construction | 2025 |
| Loveyoursoil Ltd | Wholesale & retail | 2025 |
| Loving Life - Connected Essentials Ltd | Hospitality | 2024 |
| LS Web Development Ltd | Professional & scientific | 2026 |
| LSC Beauty and Laser Limited | Other services | 2025 |
| Lubna Rafiq Ltd | Other services | 2011 |
| Lucas Dinh Ltd | Other services | 2021 |
| Lucid Business Services Limited | Administrative & support | 1998 |
| Luckypoppy Limited | Information & communication | 2026 |
| Lucy Webster Limited | Information & communication | 2021 |
| Lullabed Ltd | Manufacturing | 2022 |
| Lunsar Limited | Professional & scientific | 2021 |
| Lupus Court Residents Association Limited | Households | 1974 |
| Luzar Distribution Ltd | Wholesale & retail | 2026 |
| Lyndhurst Rest Home Limited | Health & social care | 2008 |
| M & S Foster Properties Limited | Real estate | 2003 |
| M DE Freitas Ltd | Professional & scientific | 2026 |
| M T Agencies Limited | Other services | 2018 |
| M T C S Consulting Limited | Financial services | 2017 |
| M&S City Homes Ltd | Real estate | 2024 |
| M.M.A. Construction Limited | Construction | 2005 |