| Lady on the Ladder Ltd | Administrative & support | 2023 |
| LAJ Mendsco Limited | Health & social care | 2026 |
| Lakky Physio Limited | Health & social care | 2009 |
| Lamb Brooks LLP | | 2011 |
| Lamb Brooks Services Limited | Professional & scientific | 2012 |
| Lamb Brooks Solicitors Ltd | Professional & scientific | 2026 |
| Lamb Brooks Trustees Limited | Professional & scientific | 2004 |
| Lamma Griffin Ltd | Financial services | 2022 |
| Lanbeau Comms Limited | Information & communication | 2015 |
| Lancashire (Fork Truck) Services Limited | Extraterritorial | 2009 |
| Landers Management Ltd | Information & communication | 2024 |
| Landmark Development Consultants Ltd | Professional & scientific | 2022 |
| Lang & Horgan Limited | Professional & scientific | 2009 |
| Lansdowne Property Management Ltd | Real estate | 2023 |
| Lantenna Ltd | Information & communication | 2025 |
| Lapco Consultancy Ltd | Health & social care | 2014 |
| LAR Logistic Ltd | Transport & logistics | 2024 |
| Lasborough Holdings Limited | Arts & recreation | 2024 |
| Lastframe Consultants Limited | Professional & scientific | 2024 |
| Latitude 91 Limited | Information & communication | 2006 |
| Laurentiu George Pastor UK Ltd | Transport & logistics | 2017 |
| Laurol Marketing Limited | Administrative & support | 2002 |
| Lavazza Professional UK Limited | Manufacturing | 2008 |
| Lavazza Professional UK Operating Services Limited | Hospitality | 2020 |
| Laverstoke Park Farm Limited | Professional & scientific | 2005 |
| Lawmens Security Ltd | Administrative & support | 2026 |
| Lawn in Order Ltd | Administrative & support | 2025 |
| Lawnscience (North Hampshire) Ltd | Administrative & support | 2021 |
| Lawrence Young Financial Management Limited | Real estate | 2008 |
| Lawrence Young Limited | Professional & scientific | 2002 |
| Lawyer on Site Ltd | Professional & scientific | 2012 |
| Laxant Limited | Information & communication | 2011 |
| Laxant Properties Limited | Real estate | 2022 |
| Layer Zero Services Limited | Information & communication | 2017 |
| Layerzero Signals Ltd | Information & communication | 2025 |
| Lazar SIA & Company Ltd | Transport & logistics | 2021 |
| Lazdot Ltd | Information & communication | 2022 |
| Lazerlogic (Europe) Limited | Wholesale & retail | 2014 |
| Lazerlogic Limited | Wholesale & retail | 2014 |
| Lazy Moon Drinks Ltd | Manufacturing | 2025 |
| LB (GB) Ltd | Financial services | 2009 |
| Lbee Capital Ltd | Professional & scientific | 2025 |
| LC Autocare Ltd | Wholesale & retail | 2019 |
| LC Cladding Systems Limited | Construction | 2012 |
| LC Services (Building) Ltd | Construction | 2014 |
| Lcbcm Ltd. | Real estate | 2019 |
| LCS Electrical Distributors UK Ltd | Wholesale & retail | 2017 |
| Ldbernasconi Limited | Professional & scientific | 2012 |
| LE Roux Rentals Ltd | Real estate | 2024 |
| Lead Agile Limited | Information & communication | 2021 |
| Lead Insight Ltd | Information & communication | 2014 |
| Leadus Limited | Transport & logistics | 2007 |
| Leamington Court Newfound Management Ltd | Households | 2018 |
| Leanspirited Limited | Information & communication | 2025 |
| Leapling Consulting Limited | Professional & scientific | 2019 |
| Learn Nest Education Ltd | Education | 2024 |
| Learn With Jomcy Ltd | Administrative & support | 2022 |
| Leasch Investments Limited | Real estate | 1961 |
| Lease Management Services Limited | Financial services | 2018 |
| Leate Consulting Limited | Information & communication | 2000 |
| LED Futures Limited | Wholesale & retail | 2017 |
| LEE Consulting Services Ltd | Professional & scientific | 2023 |
| LEE Cunningham Civil Engineering Limited | Administrative & support | 2010 |
| Lee-Buckland & Daughters Ltd | Extraterritorial | 2024 |
| Leeds City Dentalcare Limited | Health & social care | 2008 |
| Legacy Home Contractors Ltd | Construction | 2025 |
| Legacy Scaffolding Services Limited | Construction | 2023 |
| Lehocki Engineering & Consulting Ltd | Professional & scientific | 2015 |
| Leisure Links International Limited | Arts & recreation | 2000 |
| Leit 1 Limited | Professional & scientific | 1930 |
| LEN R. Raynsford & SON Limited | Construction | 1997 |
| Lendocare Ltd | Other services | 2024 |
| Lenton Wecc Ltd | Real estate | 2021 |
| LEO Mulkerns Architects Ltd | Professional & scientific | 2001 |
| Leonard Wealth Solutions Ltd | Financial services | 2018 |
| Leong Property Ltd | Real estate | 2024 |
| Leonna Salmon Financial Planning Ltd | Financial services | 2021 |
| LEP 2012 Ltd | Professional & scientific | 2012 |
| Lesley, Stephen & Co. Limited | Financial services | 2010 |
| Letcom Property Development Limited | Real estate | 2014 |
| Leve Ltd | Other services | 2024 |
| Leverne Consultancy Ltd | Professional & scientific | 2016 |
| Levertonhelm (Holdings) Limited | Manufacturing | 2010 |
| Levertonhelm Contracts Limited | Manufacturing | 1982 |
| Levertonhelm Limited | Manufacturing | 1976 |
| Levo Electrical Ltd | Construction | 2026 |
| Lewis Investment Services Ltd | Professional & scientific | 2020 |
| LFM Plumbing and Heating Ltd | Construction | 2023 |
| LG Courier Service Ltd | Transport & logistics | 2016 |
| LGL COX Limited | Real estate | 2008 |
| LH International Ltd | Professional & scientific | 2021 |
| Lhfx Limited | Information & communication | 2016 |
| LHK Ltd. | Professional & scientific | 2013 |
| LHR Car Services Ltd | Transport & logistics | 2023 |
| Liberate Enterprises Ltd | Construction | 2020 |
| Life Right UK Limited | Health & social care | 2006 |
| Lifetime Estate Planning Limited | Professional & scientific | 2005 |
| Lift Management Support Services Ltd | Administrative & support | 2024 |
| Lightfeet Consulting Limited | Professional & scientific | 2016 |
| Lighthouse Accounting Services Limited | Professional & scientific | 2019 |