| Leia Investments Ltd | Real estate | 2021 |
| Leia Property Lettings Ltd | Real estate | 2024 |
| Leicester Media Group Ltd | Wholesale & retail | 2026 |
| Leila Trans Ltd | Transport & logistics | 2023 |
| Leisure Club Developments Limited | Extraterritorial | 2025 |
| Leisure Parks Estates LLP | | 2009 |
| Leisure Parks Group Limited | Financial services | 2022 |
| Leisure Parks Investments Limited | Administrative & support | 2009 |
| Leisure Parks Luxury Living Limited | Hospitality | 2017 |
| Leisure Parks Luxury Services Limited | Hospitality | 2019 |
| Leisure Parks Real Estate (Holdings) Limited | Financial services | 2013 |
| Leisure Parks Real Estate Limited | Hospitality | 2007 |
| LEM Productions Ltd | Information & communication | 2024 |
| Lememory Ltd | Wholesale & retail | 2016 |
| Lemoi Mares Limited | Other services | 2017 |
| Lemon AI Limited | Information & communication | 2021 |
| Lemon Nook Limited | Manufacturing | 2021 |
| Lend IT Ltd | Information & communication | 2025 |
| Leng Digital Media Ltd | Professional & scientific | 2020 |
| Leng Lettings Ltd | Real estate | 2020 |
| Lengus Consultancy Services Limited | Professional & scientific | 2017 |
| Lennox Legal Limited | Real estate | 2022 |
| Lennox Legal Properties Limited | Real estate | 2026 |
| Lensflair Fotos and Films Limited | Information & communication | 2024 |
| Leocadia and Sons Limited | Health & social care | 2015 |
| Leocode Limited | Information & communication | 2009 |
| Leoluso Limited | Other services | 2018 |
| Leon Detailing Ltd | Wholesale & retail | 2025 |
| Leonardo Anaesthesia Services Ltd | Health & social care | 2019 |
| Leontrans Limited | Transport & logistics | 2013 |
| Leopold Dental & Wellness Limited | Health & social care | 2025 |
| Lepore (Cambs) Ltd | Financial services | 2022 |
| Lepore Holdings Ltd | Financial services | 2022 |
| Lerod Ehcartim Limited | Transport & logistics | 2025 |
| LES Luxes Limited | Administrative & support | 2007 |
| LES Property Ltd | Real estate | 2026 |
| Lesko Homes (Skegness) Ltd. | Hospitality | 2020 |
| Lesko Park and Leisure Group Ltd | Manufacturing | 2021 |
| Lesp 4 Limited | Hospitality | 2024 |
| Lester Holdings Limited | Financial services | 2023 |
| LET Insurance Services Ltd | Information & communication | 2007 |
| LET IT Go Vending Ltd | Wholesale & retail | 2026 |
| Let's Talk Mortgages Limited | Financial services | 2014 |
| Letee Lets Limited | Real estate | 2018 |
| Letee Limited | Real estate | 2010 |
| Letters Block Management Limited | Real estate | 2024 |
| Letters Home Rentals Ltd | Real estate | 2026 |
| Letters Property Services Ltd | Real estate | 2026 |
| Letters Secretarial Services Ltd | Administrative & support | 2023 |
| Letting NOW Ltd | Real estate | 2021 |
| Leukos Real Estate Investments Limited | Professional & scientific | 2022 |
| Level One Hundred Holdings Ltd | Administrative & support | 2018 |
| Leveld Ltd | Information & communication | 2026 |
| Levelling UP Property Investment Network Ltd | Real estate | 2023 |
| Levi 5* Limited | Health & social care | 2024 |
| Levitt's Property Limited | Real estate | 2024 |
| Levvo Ltd | Construction | 2026 |
| Lewbuild Ltd | Construction | 2024 |
| Lewis & Co Consulting Ltd | Professional & scientific | 2024 |
| Lewis Crick Building Ltd | Construction | 2022 |
| Lewis CX Consulting Limited | Professional & scientific | 2023 |
| Lewis Electronics Limited | Manufacturing | 2001 |
| Lewis House Management Company Limited | Administrative & support | 1997 |
| Lewtay Training Limited | Education | 2013 |
| LEX Negata Ltd | Information & communication | 2025 |
| Lexalto Limited | Professional & scientific | 2011 |
| Lexijame Solutions Ltd | Information & communication | 2022 |
| Lexisa Ltd | Transport & logistics | 2024 |
| Lezandjezlettings Ltd | Real estate | 2026 |
| Lezzeri Ltd | Wholesale & retail | 2022 |
| Le’Re Ltd | Wholesale & retail | 2021 |
| LFS Energy Ltd | Professional & scientific | 2023 |
| LFT Consultants Limited | Administrative & support | 2025 |
| LG Design and Build Ltd | Construction | 2018 |
| LG Housing Ltd | Real estate | 2023 |
| LG Investments Limited | Real estate | 2022 |
| LG Steel Ltd | Construction | 2017 |
| LG Trans Ltd | Transport & logistics | 2018 |
| Lgado Artificial Grass Ltd | Construction | 2018 |
| LH Bourne Ltd | Other services | 2022 |
| LH Tuition Centre Limited | Education | 2019 |
| LHA Automotive Services Ltd | Wholesale & retail | 2023 |
| LHA Property Ltd | Real estate | 2021 |
| LHF Holdings Limited | Financial services | 2013 |
| LHK6/6 Ltd | Health & social care | 2021 |
| Lhsw (Churchinford) Limited | Construction | 2016 |
| Lhsw (Creech ST Michael) Limited | Construction | 2011 |
| Lhsw (Ivybridge) Limited | Extraterritorial | 2017 |
| Lhsw Churchinford Management Company Limited | Households | 2017 |
| LHWC2024 Ltd | Financial services | 2025 |
| LI Jeune Holdings Limited | Financial services | 2024 |
| LI Jeune Property Limited | Real estate | 2026 |
| LIA Security Services Ltd | Administrative & support | 2021 |
| Liam Stone Corporation Ltd | Wholesale & retail | 2024 |
| Liberty Estate Planning Limited | Financial services | 2014 |
| Liberty Partnership Holdings Ltd | Financial services | 2022 |
| Liberty Partnership Limited | Financial services | 2007 |
| Libham Projects Limited | Construction | 2012 |
| Libra Concrete Pumping Ltd | Administrative & support | 2021 |
| Libra View Ltd | Real estate | 2020 |