| London Long Fries Ltd | Hospitality | 2020 |
| London Longsword Academy Ltd | Education | 2017 |
| London Loyal Photography Ltd | Professional & scientific | 2022 |
| London Ortho Ltd | Health & social care | 2010 |
| London Power Tools & Fixings Ltd | Administrative & support | 2011 |
| London Power Tools Ltd | Administrative & support | 1997 |
| London Powerseal Ltd | Construction | 2021 |
| London Property Centre Limited | Real estate | 2015 |
| London Property Repairs Ltd | Construction | 2025 |
| London Psychology Consultants Limited | Health & social care | 2008 |
| London Relationship Clinic Ltd | Health & social care | 2024 |
| London Research International Limited | Professional & scientific | 2003 |
| London Road Estate Management Limited | Households | 2012 |
| London Road Office Furniture Ltd | Wholesale & retail | 2006 |
| London Sales Training Ltd | Other services | 2014 |
| London School of Social Enterprise and Sustainable Economics Ltd | Education | 2020 |
| London South East Academies Trust | Education | 2014 |
| London Structural Waterproofing Ltd | Construction | 2019 |
| London Surgical Agency Limited | Health & social care | 2014 |
| London Terrace Management Company Limited | Households | 1992 |
| Longlands Court Residents Association Limited | Households | 1988 |
| Lonsdale Homes Limited | Real estate | 2006 |
| Looks Lovely Limited | Construction | 2008 |
| Lopes Construction Consultancy Ltd | Professional & scientific | 2026 |
| Lorabase Consulting Limited | Administrative & support | 2022 |
| Lords Pharmacy Limited | Wholesale & retail | 1987 |
| Lore Business Solutions Limited | Information & communication | 2017 |
| Loroil Limited | Financial services | 2017 |
| Lorraine Court Management Company Limited | Households | 1999 |
| LOS Andes Ltd | Wholesale & retail | 2011 |
| Lotfi Properties Limited | Real estate | 2021 |
| LOTT1 Ltd | Real estate | 2023 |
| Lotus Linguine 2 Limited | Hospitality | 2026 |
| Lotus Wellbeing Spa Ltd | Other services | 2019 |
| Lotus Yachting Ltd | Extraterritorial | 2025 |
| Loud Mind Club Limited | Manufacturing | 2025 |
| Louis Francke (Holdings) Limited | Real estate | 1964 |
| Loumirage Ltd | Manufacturing | 2025 |
| Loup House Management Limited | Households | 1982 |
| Lourosehair Ltd | Other services | 2022 |
| Louvain Estates Ltd | Real estate | 2026 |
| Lovrent Ltd | Wholesale & retail | 2024 |
| Lower Rock Labs Ltd | Professional & scientific | 2023 |
| Lowfield Systems Limited | Information & communication | 2013 |
| Lownds Court Management Company Limited | Hospitality | 1991 |
| Loyal State Corporation Limited | Extraterritorial | 2014 |
| LP Unit Cars Ltd | Transport & logistics | 2021 |
| Lpmerch Ltd | Wholesale & retail | 2026 |
| LPS South East Limited | Administrative & support | 2017 |
| Lpullen Ltd | Professional & scientific | 2026 |
| LRJ Brand Marketing Ltd | Administrative & support | 2019 |
| LRS Homes Ltd | Construction | 2023 |
| LRT Quantity Surveying Services Ltd | Professional & scientific | 2010 |
| LS Motor Traders Ltd | Wholesale & retail | 2021 |
| LS Quotes Ltd | Other services | 2016 |
| LSP Renewables Consultancy Limited | Administrative & support | 2019 |
| LSP Renewables Limited | Administrative & support | 2017 |
| Lsse Commercial Limited | Education | 2026 |
| Lstv World Wide Ltd | Information & communication | 2026 |
| LSU Lions FC CIC | Arts & recreation | 2024 |
| Ltgi Ltd | Real estate | 2020 |
| LTO Services Ltd | Administrative & support | 2026 |
| Lualle Ltd | Professional & scientific | 2022 |
| Lubbock Court (Management) Limited | Households | 1984 |
| Lucas Construction Design & Build Ltd | Construction | 2011 |
| Lucena's Megastore Ltd | Wholesale & retail | 2021 |
| Luchi Africa Foods Ltd | Manufacturing | 2026 |
| Luchta Carpentry Ltd | Manufacturing | 2025 |
| LUD Capital Limited | Administrative & support | 2024 |
| Lukansoma Limited | Health & social care | 2013 |
| Lukasz Laski Limited | Construction | 2022 |
| Luke and Pete Ltd | Information & communication | 2023 |
| Lulu Industries Ltd | Wholesale & retail | 2022 |
| Lumalight Films Limited | Information & communication | 2025 |
| Lumenis Properties Ltd | Real estate | 2021 |
| Lumere Studios Ltd | Information & communication | 2025 |
| Luminaire Consulting Limited | Administrative & support | 2022 |
| Lumivé Medical Aesthetics Ltd | Health & social care | 2021 |
| Lumora Atelier Ltd | Wholesale & retail | 2025 |
| Lumora Partners Ltd | Real estate | 2025 |
| Luna Careers Ltd | Administrative & support | 2021 |
| Lunar Legend Ltd | Wholesale & retail | 2018 |
| Luscombe Court (Beckenham) Management Limited | Households | 1982 |
| Lush Transports Ltd | Construction | 2025 |
| Lustre Home and Garden Ltd | Other services | 2016 |
| Lutaj Ltd | Wholesale & retail | 2023 |
| LUX Property Management Group Ltd | Households | 2026 |
| Luxe Shading Co. Ltd | Professional & scientific | 2024 |
| Luxe Vision Property Group Ltd | Real estate | 2025 |
| Luxmi Properties and Construction Ltd | Real estate | 2025 |
| Luxora Tech Ltd | Wholesale & retail | 2025 |
| Luxury Chapter Home Ltd | Other services | 2026 |
| Luxury Hire Ltd | Administrative & support | 2025 |
| Luxury Home Living Ltd | Real estate | 2019 |
| Luxury Trade Ltd | Wholesale & retail | 2024 |
| LW FIC Limited | Financial services | 2023 |
| Lwaresolutions Ltd | Information & communication | 2020 |
| Lx-Qu Ltd | Professional & scientific | 2020 |
| Lynbrook Management Ltd | Professional & scientific | 2024 |
| Lynbrook PTY Limited | Real estate | 2026 |