| L7 Enterprises Limited | Real estate | 2009 |
| LAB Admin Services Ltd | Administrative & support | 2024 |
| Laith Pharma Ltd | Health & social care | 2024 |
| Lakes Financial and Bookkeeping Ltd | Administrative & support | 2019 |
| Lakha Construction Limited | Construction | 2019 |
| Laleham Computer Limited | Other services | 2021 |
| Laleham Landscapes Ltd | Administrative & support | 2024 |
| Lalo Group Limited | Other services | 2026 |
| Lamont Builds Limited | Construction | 2025 |
| Landmark Roofing Ltd | Construction | 2024 |
| Landscape Doctor Ltd | Administrative & support | 2013 |
| Landzar Ltd | Construction | 2021 |
| Lang International Limited | Professional & scientific | 2017 |
| Langford Foods Limited | Hospitality | 2026 |
| Lansdown Directorships Limited | Extraterritorial | 2009 |
| Lansweeper Software Solutions Limited | Information & communication | 2026 |
| Lantern House Developments Ltd | Construction | 2024 |
| Lantern House Residential Management Limited | Households | 2026 |
| LAO Wang Limited | Hospitality | 2022 |
| Lasrado Trade Limited | Wholesale & retail | 2026 |
| Latchmere Heating Limited | Construction | 2017 |
| Launchpad Partners Ltd | Professional & scientific | 2026 |
| Laurus Care Solutions Limited | Hospitality | 2017 |
| Law for Palestine Ltd | Professional & scientific | 2020 |
| Lawford House Management Limited | Households | 2013 |
| Laxmi Realties Ltd | Real estate | 2025 |
| Lazare Management Company Limited | Households | 1985 |
| LB2 Finances Ltd | Transport & logistics | 2021 |
| LDN Environmental Ltd | Water & waste | 2026 |
| LDN Landscaping & Construction Ltd | Administrative & support | 2026 |
| LDN Rose Ltd | Wholesale & retail | 2018 |
| LE Scaling Ltd | Professional & scientific | 2025 |
| LE Visuals Ltd | Arts & recreation | 2022 |
| Leacroft Close Investments Ltd | Real estate | 2021 |
| Leahy Design Ltd | Information & communication | 2017 |
| Lebanese Grill Ltd | Hospitality | 2026 |
| Ledream Ltd | Real estate | 2023 |
| LEE IQ Family Ltd | Transport & logistics | 2025 |
| Lees Muss Limited | Wholesale & retail | 2023 |
| Legacy Consulting & Business Services Limited | Financial services | 2014 |
| Legacy Wellness Limited | Wholesale & retail | 2025 |
| Legra Trust Services Limited | Other services | 1997 |
| Lemart Ltd | Professional & scientific | 2021 |
| Lemmanuell Ltd | Professional & scientific | 2024 |
| Lemon House Cuisine Ltd | Hospitality | 2025 |
| Lemon Zest Limited | Professional & scientific | 2010 |
| Leokai Ltd | Wholesale & retail | 2021 |
| Lerich Limited | Information & communication | 2019 |
| Leytor Limited | Households | 1983 |
| Lezan Ltd | Professional & scientific | 2015 |
| LH Lighting Design Ltd | Professional & scientific | 2025 |
| Liberty House Molesey Ltd | Other services | 2023 |
| Libertywrapz Ltd | Wholesale & retail | 2021 |
| Life Design and Build Ltd | Construction | 2025 |
| Lift Scaffolding Ltd | Construction | 2014 |
| Lift Truck Solutions Limited | Wholesale & retail | 2019 |
| Light and Dark Clothing Limited | Manufacturing | 2024 |
| Lightbulb NLP Ltd | Education | 2019 |
| Lighthouse Space Ltd | Real estate | 2024 |
| Lime Tree Apartments Ltd | Real estate | 2022 |
| Limit -CON Ltd | Administrative & support | 2017 |
| Linela Cleaning Cervices Limited | Administrative & support | 2023 |
| Link Go SCS Ltd | Transport & logistics | 2018 |
| Linksol Ltd | Information & communication | 2013 |
| Linktrans Ltd | Wholesale & retail | 2018 |
| Linx Copiers Limited | Administrative & support | 2002 |
| Lionhead Property Ltd | Households | 2020 |
| Liss Land Limited | Real estate | 2019 |
| Lite Solutions Ltd | Other services | 2025 |
| Little Blossoms Childminding Ltd | Health & social care | 2026 |
| Little Drifters Ltd | Wholesale & retail | 2026 |
| Little Stitches Mbab Ltd | Wholesale & retail | 2025 |
| Liveactive Ltd | Wholesale & retail | 2025 |
| Livelee Waste and Facilities Ltd | Water & waste | 2021 |
| LJ Brick, Fence & Groundworks. Ltd | Construction | 2025 |
| LL JOI Limited | Professional & scientific | 2023 |
| Lleshi & E Construction Ltd | Construction | 2021 |
| Llewellyn Music Consultancy Limited | Education | 2025 |
| Llmaestro Limited | Other services | 2019 |
| LM Tristar Ltd | Information & communication | 2025 |
| LMB Building Solutions Limited | Professional & scientific | 2023 |
| Loadmaster Construction Ltd | Construction | 2016 |
| Lodige (United Kingdom) Limited | Manufacturing | 1986 |
| Lodige Systems (UK) Limited | Manufacturing | 2001 |
| Logic Control Systems Ltd | Professional & scientific | 2026 |
| Logistics Central Ltd | Wholesale & retail | 2019 |
| Logistics Connect BV Ltd | Transport & logistics | 2023 |
| Lokilax Ltd | Information & communication | 2025 |
| Lokman 29 Ltd | Hospitality | 2026 |
| Lomas & Sons Specialist Building Materials Ltd | Wholesale & retail | 2026 |
| Londinium Property Management Limited | Professional & scientific | 2006 |
| Londis Stanwell Limited | Wholesale & retail | 2023 |
| London & Suffolk Holdings Limited | Financial services | 2017 |
| London & Suffolk Properties Limited | Real estate | 2000 |
| London and Marlborough Mallard Court Limited | Real estate | 2024 |
| London and Marlborough Reading Limited | Financial services | 2025 |
| London Chauffeur Services Ltd | Transport & logistics | 2026 |
| London City Builders & Contractors Limited | Construction | 2010 |
| London Electrical Developments Ltd | Construction | 2023 |
| London Express Drive Ltd | Wholesale & retail | 2018 |