| LD Plastering Services Limited | Construction | 2023 |
| LDN PUB Company Ltd | Administrative & support | 2023 |
| LDS Joinery Limited | Manufacturing | 2011 |
| LE Cafe Automatique Limited | Information & communication | 2011 |
| LE Omni Ltd | Real estate | 2016 |
| Leading Edge Strategy Consulting Limited | Other services | 2016 |
| Leadopulence Ltd | Administrative & support | 2023 |
| Leafbit Limited | Information & communication | 2025 |
| Leafstorm Limited | Information & communication | 2000 |
| Lean Operations Ltd | Professional & scientific | 2023 |
| Leap AI Limited | Information & communication | 2025 |
| Leapfrog A.I. Ltd | Information & communication | 2024 |
| Learn and Grow Tuition Ltd | Education | 2019 |
| Learning by Design Limited | Other services | 2009 |
| Leatherhead and District Chamber of Commerce Limited | Other services | 1999 |
| Leaver Design Ltd | Professional & scientific | 2022 |
| LED Healthcare Ltd | Health & social care | 2023 |
| Ledgora Ltd | Professional & scientific | 2025 |
| LEE M 82 Ltd | Information & communication | 2018 |
| LEE Mawdsley Photography Limited | Other services | 2003 |
| LEE Reid Limited | Professional & scientific | 2024 |
| Leeside Court Management Limited | Real estate | 2000 |
| Legacy Broadcast Communications Limited | Extraterritorial | 1985 |
| Legacy Broadcast Group Holdings Limited | Professional & scientific | 2015 |
| Legacy Broadcast International Limited | Manufacturing | 1986 |
| Legacy Haulage Services Limited | Transport & logistics | 2010 |
| Legacy Paving and Landscaping Ltd | Administrative & support | 2021 |
| Legai AI Group Limited | Information & communication | 2025 |
| Legal AI Limited | Professional & scientific | 2023 |
| Legal AI Solutions Limited | Information & communication | 2023 |
| Legalai Group Limited | Information & communication | 2026 |
| Legatum Estates Ltd | Real estate | 2021 |
| Legion Electrical Ltd | Construction | 2025 |
| Leigh Grant Consulting Ltd | Professional & scientific | 2013 |
| Leisureplan International Limited | | 1984 |
| Lemonadegolfclub Ltd | Professional & scientific | 2024 |
| Lenawee Limited | Real estate | 2010 |
| Lengthorn Consultancy Ltd | Information & communication | 2018 |
| LEO Technology Limited | Administrative & support | 2023 |
| Leonard Construction & Design Limited | Construction | 2011 |
| Leopold 36 Limited | Households | 1998 |
| Leora Foods Ltd | Hospitality | 2024 |
| Lesh Wear Ltd | Manufacturing | 2022 |
| Leslie Isles Limited | Professional & scientific | 2018 |
| LET US Spray London Limited | Construction | 2021 |
| Letterland International Ltd | Other services | 1981 |
| Leveche Associates Limited | Other services | 2018 |
| Level 5 Construction Ltd | Construction | 2018 |
| Levsec Limited | Administrative & support | 2014 |
| Lewin & Sons Limited | Construction | 2016 |
| LEX Moventur Ltd | Administrative & support | 2026 |
| Lexaro Financial Consulting Ltd | Professional & scientific | 2015 |
| Lexholmes Estates Limited | Construction | 1983 |
| Lexi Construction Ltd | Construction | 2017 |
| Lexus (GB) Limited | Wholesale & retail | 1990 |
| Lezzet London Ltd | Hospitality | 2023 |
| LEÀ Solais Limited | Manufacturing | 2022 |
| LG Accounts Limited | Professional & scientific | 2003 |
| Lglm Limited | Financial services | 2014 |
| Lhbs Invest Ltd | Real estate | 2026 |
| Liaison Communications Limited | Professional & scientific | 2003 |
| Liam & Matthew Workshop Ltd | Hospitality | 2023 |
| Liam Kirby Quantity Surveying Services Ltd | Professional & scientific | 2011 |
| Liana Investments Limited | Administrative & support | 2023 |
| Libaas Collection Ltd | Wholesale & retail | 2020 |
| Lifebond Limited | Construction | 2015 |
| Lifecarers Limited | Health & social care | 2004 |
| Lifeline PLC | Health & social care | 1987 |
| Lifepath Recruitment Ltd | Administrative & support | 2025 |
| Lifestyle Property Surrey Limited | Real estate | 2024 |
| Lifestyle Studio Surrey Limited | Arts & recreation | 2010 |
| Lifewise Lifeplanning Ltd | Information & communication | 2025 |
| Lift Motors Ltd | Wholesale & retail | 2025 |
| Light-Your-Garden Limited | Construction | 2013 |
| Ligia Schuurman Limited | Administrative & support | 2024 |
| LIH Ltd | Arts & recreation | 2024 |
| Lili Food Club Ltd | Wholesale & retail | 2023 |
| Lillygrace Investments Ltd | Real estate | 2023 |
| Lillygrace Properties Ltd | Real estate | 2023 |
| Lilu Ventures Limited | Real estate | 2015 |
| Lily PAD Play Therapy Limited | Health & social care | 2018 |
| Lime Building Limited | Construction | 2008 |
| Lime Designs Contracts Limited | Manufacturing | 2017 |
| Lime Designs Kitchens & Joinery Limited | Wholesale & retail | 2017 |
| Lime ICO Ltd | Information & communication | 2025 |
| Lime Installations Limited | Construction | 2024 |
| Liminal 11 Limited | Information & communication | 2017 |
| Limpeza (UK) Ltd | Administrative & support | 2005 |
| Limpeza Cleaning Solutions Limited | Administrative & support | 2022 |
| Linda Bloomfield Limited | Administrative & support | 2013 |
| Linea Bakery Ltd | Wholesale & retail | 2023 |
| Linea HO Ltd | Other services | 2023 |
| Linea Holdco Ltd | Hospitality | 2023 |
| Linea Investco Ltd | Financial services | 2023 |
| Lining Sector Limited | Water & waste | 2012 |
| Link Accounting Services Ltd | Administrative & support | 2011 |
| Links Into Spanish Ltd | Education | 2012 |
| Linksgage Ltd | Administrative & support | 2025 |
| Linnet and Siskin Court Residents Association Limited | Real estate | 1988 |
| Linney Fencing Limited | Construction | 1955 |