| Lemuel & Sons Ltd | Real estate | 2020 |
| Lemur Capital Ltd | Financial services | 2026 |
| Lena Lepai Beauty & Aesthetics Limited | Other services | 2024 |
| Lenards of Covent Garden Limited | Wholesale & retail | 2002 |
| Lenborough Road Residents (Buckingham) Limited | Real estate | 2000 |
| Lendaline Business Finance Ltd | Financial services | 2022 |
| Lenya J Limited | Real estate | 2016 |
| Lenya Limited | Wholesale & retail | 2016 |
| Lenz Properties Limited | Real estate | 2022 |
| LEO & Leona Investments Limited | Education | 2017 |
| LEO Enterprises Ltd | Professional & scientific | 2008 |
| LEO Express Logistics Ltd | Wholesale & retail | 2021 |
| LEO GJ Buildings South Ltd | Construction | 2024 |
| LEO Systems UK Limited | Other services | 2023 |
| LEO Ventures and Consulting Ltd | Real estate | 2011 |
| Leon Ellis Properties Limited | Real estate | 2025 |
| Leon Kushen Global Limited | Professional & scientific | 2024 |
| Leondan Transport Ltd | Wholesale & retail | 2017 |
| Leosoft Solutions Ltd | Information & communication | 2018 |
| Leotech Systems Ltd | Information & communication | 2013 |
| Lepc Limited | Information & communication | 2016 |
| Lerato's Ambition Ltd | Health & social care | 2014 |
| Lernen Bidco Limited | Financial services | 2018 |
| Lernen Bondco 2 PLC | Financial services | 2022 |
| Lernen Bondco PLC | Financial services | 2018 |
| Lernen Cleanco Limited | Financial services | 2018 |
| Lernen Midco 2 Limited | Financial services | 2018 |
| Lesley Cutler Bridal Wear Limited | Manufacturing | 2011 |
| Lesluxcatering Ltd | Hospitality | 2024 |
| Leso Management Services Limited | Professional & scientific | 2012 |
| Lesser Spotted Limited | Information & communication | 2026 |
| LET by Ltd | Real estate | 2019 |
| LET ME Handle This Limited | Arts & recreation | 2020 |
| LET Secure Ltd | Households | 2026 |
| LET1 Property LLP | | 2022 |
| Leto Ltd | Professional & scientific | 2024 |
| Letoyah Limited | Health & social care | 2024 |
| Lets-Store Ltd | Hospitality | 2012 |
| Letsletit Limited | Real estate | 2000 |
| Letstrade.Com Limited | Hospitality | 2005 |
| Letsxl Limited | Financial services | 2002 |
| Letterhouse Productions Ltd | Professional & scientific | 2020 |
| Letting My Driveway Ltd | Real estate | 2024 |
| Letts Rent (MK) Ltd | Real estate | 2005 |
| Letty Elite Ltd | Wholesale & retail | 2026 |
| Letworks Spaces Ltd | Real estate | 2025 |
| Let’S Just LET Ltd | Real estate | 2025 |
| LEU Design & Build Ltd | Construction | 2025 |
| LEV3L Access Hire & Sales Ltd | Construction | 2023 |
| LEV3L Products Limited | Construction | 2016 |
| Levangre Ltd | Wholesale & retail | 2025 |
| Level Architect Ltd | Professional & scientific | 2018 |
| Level Contracting Services Limited | Construction | 2002 |
| Level Finish Ltd | Construction | 2019 |
| Level X NDT Limited | Wholesale & retail | 2014 |
| Level-Up Lettings Ltd | Real estate | 2025 |
| LEVEL3TECH Ltd | Wholesale & retail | 2024 |
| Leveli Consulting Ltd | Professional & scientific | 2021 |
| Leveli Ltd | Wholesale & retail | 2019 |
| Levene Brickwork Ltd | Construction | 2008 |
| Levo Limited | Information & communication | 2007 |
| Levu Ltd | Professional & scientific | 2025 |
| Lewdon Limited | Real estate | 2024 |
| Lewis Brothers DRY Lining Ltd | Construction | 2014 |
| Lewis Christopher Limited | Other services | 2001 |
| Lewis Moberly Design Limited | Professional & scientific | 1987 |
| LEX Juris Investments Ltd | Administrative & support | 2025 |
| Lexag UK Limited | Professional & scientific | 2022 |
| Lexi Trans Ltd | Transport & logistics | 2023 |
| Lexis Property Limited | Real estate | 2026 |
| Lexsys Solutions Limited | Information & communication | 2010 |
| Leycroft Property Ltd | Real estate | 2023 |
| Leyland Motors Limited | Manufacturing | 2023 |
| Leys Limited | Households | 2023 |
| LF Speed Transport Limited Limited | Transport & logistics | 2021 |
| LFP Sustainable Turf Solutions Limited | Administrative & support | 2023 |
| LG Beauty Aesthetics Ltd | Other services | 2026 |
| LG Decorating Limited | Construction | 2010 |
| LGI Logistics Group International UK Limited | Transport & logistics | 2010 |
| Lgrs Universal Ltd | Construction | 2011 |
| LH Engineering Group Limited | Manufacturing | 2025 |
| LHE Consulting Ltd | Professional & scientific | 2022 |
| LHR Therapy Ltd | Health & social care | 2021 |
| Li'L BEN Coffee House Ltd | Hospitality | 2025 |
| LIA Maguraushe Holdings Ltd | Real estate | 2025 |
| Liam-Jay Entertainment Operations Ltd | Arts & recreation | 2024 |
| Liangl KJ Ltd. | Wholesale & retail | 2025 |
| Lianne Sanderson Limited | Information & communication | 2021 |
| Liao ZE KJ Ltd. | Wholesale & retail | 2025 |
| Liatay Ltd | Administrative & support | 2024 |
| Liberating Estates Ltd | Real estate | 2024 |
| Libertescents Ltd | Extraterritorial | 2024 |
| Liberty Educare London Limited | Education | 2019 |
| Liberty House Construction Management Limited | Professional & scientific | 2023 |
| Liberty Integrated Care Ltd | Professional & scientific | 2018 |
| Liberty's Haus Ltd | Wholesale & retail | 2026 |
| Libiyé Tech Limited | Information & communication | 2017 |
| Libra (Longhurst Group) Treasury NO 2 PLC | Real estate | 2018 |
| Libra (Longhurst Group) Treasury PLC | Real estate | 2012 |
| Librios Limited | Information & communication | 1995 |