| Lastra & Hout Limited | Wholesale & retail | 2019 |
| Lastra Property Group Ltd | Real estate | 2022 |
| Latibree Limited | Administrative & support | 2009 |
| Laundrylux Holdings Limited | Other services | 2023 |
| Laundrylux Ltd | Other services | 2023 |
| Laura Beckett Limited | Construction | 2017 |
| Laurelin Investments (UK) Limited | Administrative & support | 2024 |
| Laurence Lettings Limited | Real estate | 2023 |
| Laurence Myers Limited | Information & communication | 1982 |
| Laurence Taylor UK Holdings Ltd | Administrative & support | 2023 |
| Lawes Recruitment (UK) Group Limited | Administrative & support | 2012 |
| Lawrence UK LLP | | 2009 |
| Laybrick Investments UK Ltd | Real estate | 2024 |
| Laydan Limited | Households | 2025 |
| Lazer HBC Ltd | Administrative & support | 2024 |
| LBW Solutions Ltd | Professional & scientific | 2012 |
| LCC Designs Ltd | Wholesale & retail | 2022 |
| LDD Construction Limited | Construction | 2009 |
| LDD Fire Protection Ltd. | Construction | 2009 |
| LDD Holdings Limited | Financial services | 2025 |
| LDP Mark Ltd | Administrative & support | 2020 |
| LDS Trowbridge Ltd | Hospitality | 2023 |
| Le-Curve Limited | Administrative & support | 2022 |
| Lead Consultancy Services Ltd | Information & communication | 2012 |
| Lead Digital Limited | Professional & scientific | 2019 |
| Lead Wear Ltd | Manufacturing | 2020 |
| Lead-Tech Roofing Limited | Construction | 1992 |
| Leading Developments N & D Limited | Real estate | 2021 |
| Leadpm Ltd | Administrative & support | 2022 |
| Leafcity Holdings Limited | Real estate | 2016 |
| Leaflace Limited | Wholesale & retail | 1999 |
| Leafwild Ltd | Wholesale & retail | 2016 |
| Lealana Events Ltd | Hospitality | 2024 |
| Lean Consulting Limited | Professional & scientific | 2007 |
| LEE Bilsby Limited | Administrative & support | 2009 |
| LEE Bonnick Limited | Professional & scientific | 2016 |
| LEE Simon Day Ltd | Extraterritorial | 2023 |
| Lee-Bramble High Class Homes Ltd | Real estate | 2017 |
| Leeming Pilkington Limited | Hospitality | 2001 |
| Lefils Project Management Limited | Administrative & support | 2025 |
| Legacy Investment Ventures Limited | Real estate | 2025 |
| Legacy London Developments Limited | Construction | 2021 |
| Legacy Protect Property Ltd | Real estate | 2020 |
| LEGAL4RECRUITMENT Consultancy Services Limited | Professional & scientific | 2010 |
| Legend Turkish Barber Ltd | Other services | 2017 |
| Legsly Limited | Wholesale & retail | 2023 |
| Leicester City Dining Ltd | Hospitality | 2025 |
| Leka Ltd | Administrative & support | 2014 |
| Lemon Seed Ltd | Hospitality | 2019 |
| Lentifx Ltd | Financial services | 2024 |
| LEO Ninel Group Ltd | Construction | 2024 |
| LEO Risk Consulting Limited | Administrative & support | 2014 |
| Leonards Management Limited | Households | 2023 |
| LET IT Rain Limited | Administrative & support | 2010 |
| Let's GET Down to Quizness Limited | Other services | 2020 |
| Lets Invent Limited | Information & communication | 2022 |
| Levant Designs Limited | Construction | 2016 |
| Level the Field Ltd | Professional & scientific | 2024 |
| Leverton House (Woodford Green) Limited | Real estate | 2022 |
| Levicki Osteopathy Limited | Health & social care | 2017 |
| Levicki Property Limited | Construction | 2018 |
| Lewin Physio Ltd | Health & social care | 2018 |
| Lewis Groundwork Ltd | Construction | 2025 |
| Lewis Paige Recruitment Limited | Administrative & support | 2011 |
| Lexa Casa Limited | Financial services | 2026 |
| Leyon Properties Ltd | Real estate | 2017 |
| Leyton Group Ltd | Construction | 2011 |
| Leyton Orient Women E10 Limited | Arts & recreation | 2025 |
| Leytonstone Properties 2020 Ltd | Real estate | 2020 |
| Leytonstone Properties LLP | | 2007 |
| LF Gallagher Ltd | Administrative & support | 2019 |
| LG Smith Ltd | Professional & scientific | 2022 |
| LGM Performing Arts Ltd | Arts & recreation | 2019 |
| LHF Aylesbury Ltd | Real estate | 2026 |
| Li&Mar Ltd | Construction | 2016 |
| Liako Ltd | Professional & scientific | 2023 |
| Liaranne Investments Ltd | Administrative & support | 2019 |
| Liber Events Ltd | Hospitality | 2019 |
| Liberty Ilford Holdings Limited | Construction | 2016 |
| Libya UK Alliance Ltd | Professional & scientific | 2026 |
| Life Box Limited | Wholesale & retail | 2018 |
| Life Cleaning Services Limited | Administrative & support | 2015 |
| Lifestyle Care and Community Limited | Health & social care | 2022 |
| Lifting DAD Ltd | Arts & recreation | 2023 |
| Lighting With Design Ltd | Construction | 2021 |
| Lightman & Co Limited | Administrative & support | 2011 |
| Lights Control Ltd | Other services | 2013 |
| Lilys Place Limited | Hospitality | 2013 |
| Lime Properties Management Ltd | Real estate | 2025 |
| Limitlease Limited | Professional & scientific | 2003 |
| LIN Ryan Construction Limited | Construction | 2023 |
| Lincoln Spice Limited | Hospitality | 2018 |
| Lindersfield Childrens Home Ltd | Health & social care | 2024 |
| LINE4 Ltd | Information & communication | 2026 |
| Linfeld Ltd | Financial services | 2019 |
| Linvatom Transport Ltd | Transport & logistics | 2014 |
| Lipkin Limited | Wholesale & retail | 2011 |
| Liquid Vape Store Limited | Wholesale & retail | 2018 |
| Liquidae Limited | Administrative & support | 2015 |
| Lisa Grace Ltd | Professional & scientific | 2016 |