| Leading Prospects Limited | Professional & scientific | 2025 |
| Leadway Consulting Limited | Professional & scientific | 2017 |
| Leaf One Ltd | Information & communication | 2021 |
| Leaman Consultancy Ltd | Administrative & support | 2026 |
| Leamington and Goostrey Management Services LLP | | 2015 |
| Leanda Heler Limited | Professional & scientific | 2020 |
| Leaner Mirrors Limited | Wholesale & retail | 2021 |
| Leap Organisation Ltd | Professional & scientific | 2004 |
| Learn Space Ltd | Education | 2025 |
| Learning Chronicles Ltd | Information & communication | 2025 |
| Leaside Properties Ltd | Real estate | 2026 |
| Leaville Ltd | Extraterritorial | 2006 |
| Lebensraum Limited | Real estate | 2025 |
| Lebo Services Ltd | Real estate | 2021 |
| Lecture Hall Management Company Limited | Households | 2023 |
| LEE & LOU Limited | Manufacturing | 2025 |
| LEE Martin Lighting Limited | Information & communication | 2009 |
| LEE Richardson Ltd | Professional & scientific | 2022 |
| Leeds Assets (NO 2) Limited | Extraterritorial | 2009 |
| Leeds Assets Limited | Extraterritorial | 2009 |
| Leeds Estate II Ltd | Other services | 2017 |
| Leeds Estates Ltd | Extraterritorial | 2017 |
| Leeds Management Limited | Hospitality | 2018 |
| Legacy Pillar Properties Ltd | Real estate | 2025 |
| Legal Outsource Support Services Limited | Administrative & support | 2023 |
| Legend Quays Limited | Other services | 2018 |
| Legtest Ltd | Professional & scientific | 2020 |
| Lehadlik Ltd | Wholesale & retail | 2017 |
| Lehoydoys Ltd | Other services | 2020 |
| Leia Acquisition Limited | Financial services | 2024 |
| Leicester Group Ltd | Real estate | 2026 |
| Leicester Terrace Ltd | Real estate | 2019 |
| Leitner's Ltd | Administrative & support | 2015 |
| LEJ Consulting (NW) Ltd | Administrative & support | 2015 |
| LEK Property Limited | Real estate | 2024 |
| Leluxe Ltd | Real estate | 2021 |
| Lembray Ltd | Information & communication | 2026 |
| Lemmana Limited | Information & communication | 2017 |
| Lemville Ltd | Extraterritorial | 2008 |
| Lengz Ltd | Wholesale & retail | 2026 |
| Lennox Portland Ltd | Manufacturing | 2021 |
| Lenrock Limited | Real estate | 1988 |
| Lens Flare TV Ltd | Information & communication | 2016 |
| Lens Pro Ltd | Wholesale & retail | 2026 |
| Lenslocker Limited | Professional & scientific | 2025 |
| LEO & Roobs Ltd | Hospitality | 2024 |
| LEO Jack Ltd | Administrative & support | 2020 |
| Leon DEL Cabo Limited | Arts & recreation | 2026 |
| Leonard Curtis Sheffield Limited | Extraterritorial | 2015 |
| Leowenisha Ltd | Hospitality | 2026 |
| Lescano Property Limited | Real estate | 2024 |
| Lescanodigital Limited | Information & communication | 2024 |
| Lestam Ltd | Construction | 2018 |
| Lesters Nursery World Limited | Wholesale & retail | 2003 |
| Lesters Nurseryworld (Manchester) Ltd | Real estate | 2023 |
| Let's Go NOW Limited | Hospitality | 2025 |
| Let's Press Ltd | Professional & scientific | 2024 |
| Letready Property Services Ltd | Construction | 2025 |
| Lets Drive Road School Ltd | Education | 2025 |
| Lett's Code Ltd | Information & communication | 2021 |
| Letters of Note Ltd | Wholesale & retail | 2012 |
| Leummol Ltd | Real estate | 2020 |
| LEV Chaim | Other services | 2020 |
| LEV Shomeia - a Listening Heart Ltd | Other services | 2008 |
| Leveled Maintenance Ltd | Construction | 2025 |
| Leveltenten Fire Consultancy Ltd | Professional & scientific | 2026 |
| Lever Macs Ltd | Extraterritorial | 2019 |
| Levett Road Ltd | Real estate | 2026 |
| Levii Ltd. | Arts & recreation | 2017 |
| Levitate Recruitment Limited | Administrative & support | 2012 |
| Levito Ltd | Real estate | 2019 |
| Lewis & Co. Financial Services Ltd | Professional & scientific | 2025 |
| LEX Collective Ltd | Wholesale & retail | 2026 |
| LEX Wigs Ltd | Health & social care | 2022 |
| Lexend Limited | Real estate | 2025 |
| Lexer Trading Ltd | Wholesale & retail | 2024 |
| Lexet Ltd | Professional & scientific | 2021 |
| Lexvue Limited | Professional & scientific | 2025 |
| Lezamer Ltd | Health & social care | 2020 |
| LF Administration Ltd | Administrative & support | 2018 |
| LF Europe Limited | Professional & scientific | 1974 |
| LF Europe Trading Limited | Administrative & support | 2004 |
| LF Fashion Limited | Wholesale & retail | 1981 |
| LFO Studios Ltd | Professional & scientific | 2026 |
| LHL Trading Group UK Limited | Wholesale & retail | 2016 |
| LI & Fung (Europe) Holding Limited | Professional & scientific | 1937 |
| Lialoc Ltd | Construction | 2024 |
| Libby Smith Limited | Health & social care | 2011 |
| Liberties Development Limited | Construction | 2011 |
| Liberty Healthcare Services Ltd | Health & social care | 2025 |
| Librayanga Ltd | Health & social care | 2025 |
| Libya OIL Eritrea Limited | Administrative & support | 1993 |
| Libya OIL Sudan Limited | Administrative & support | 1924 |
| Lichbury Estates Ltd | Real estate | 2017 |
| Liege & Lief Limited | Professional & scientific | 2022 |
| Life Lodge Ltd | Education | 2022 |
| Life MJF Ltd | Professional & scientific | 2026 |
| Life Skills for Home Community Interest Company | Health & social care | 2024 |
| Lifecams Limited | Information & communication | 2018 |
| Lifedove Limited | Real estate | 2022 |