| Lazy Lucy Ltd | Wholesale & retail | 2017 |
| LB Consultancy Limited | Professional & scientific | 2005 |
| LB Prime Build Ltd | Construction | 2025 |
| LB Resourcing Ltd | Information & communication | 2022 |
| LB Trade Limited | Professional & scientific | 2010 |
| LBI Group Ltd | Construction | 2023 |
| Lblh Ltd | Real estate | 2018 |
| LC Fowler Construction Limited | Construction | 2022 |
| LCF Testing Limited | Professional & scientific | 2024 |
| LCM Brickwork Ltd | Construction | 2026 |
| LCM Healthcare Private Limited | Professional & scientific | 2012 |
| LCR Carpentry Limited | Construction | 2023 |
| LD Retail Management Limited | Information & communication | 2022 |
| LD8 Consulting Ltd | Professional & scientific | 2016 |
| LDM Installations Ltd | Construction | 2024 |
| LDN Safety Ltd | Professional & scientific | 2019 |
| LDW General Construction Ltd | Construction | 2026 |
| LE4D Property Ltd | Real estate | 2023 |
| Leader Petroleum Limited | Real estate | 1978 |
| Leadership Dynamics Ltd | Professional & scientific | 2018 |
| Leadersmith Consulting Ltd | Administrative & support | 2020 |
| Leading Edge Associates Ltd | Health & social care | 2025 |
| Leaf & Stone Landscapes Ltd | Professional & scientific | 2025 |
| Leafy Reach Co Ltd | Real estate | 2024 |
| Lean Bay Limited | Information & communication | 2021 |
| Leanne Page Limited | Arts & recreation | 2022 |
| Learnthrive Ltd | Education | 2025 |
| Lecter Associates Limited | Professional & scientific | 1999 |
| Lecter Limited | Construction | 2006 |
| Leed Creative Ltd | Wholesale & retail | 2013 |
| Leeswood Developments Limited | Real estate | 2024 |
| Legacy Auto Garage Limited | Wholesale & retail | 2022 |
| Legacy Elite Auto Repair Centre Ltd | Manufacturing | 2024 |
| Legacy Fiduciary Services Holdings (UK) Limited | Professional & scientific | 2024 |
| Legacy Funeral Services Limited | Other services | 2019 |
| Legacy Products Limited | Wholesale & retail | 2003 |
| Legal Lens Solutions Ltd | Administrative & support | 2020 |
| Legal Wisdom Limited | Professional & scientific | 2023 |
| Legatum Properties Ltd | Real estate | 2022 |
| Legende Automobiles Limited | Manufacturing | 2024 |
| Legge-Work Consultancy Ltd | Professional & scientific | 2025 |
| Legion Fleet Services Ltd | Wholesale & retail | 2026 |
| Lemon Loans Limited | Professional & scientific | 2025 |
| Lemon Suites Limited | Real estate | 1988 |
| Lemoni Enterprises UK Ltd | Hospitality | 2018 |
| Lemoni Holdings Ltd | Hospitality | 2018 |
| Lemoni the Bull Ltd | Hospitality | 2020 |
| Lemoni the Jekyll & Hyde Ltd | Hospitality | 2020 |
| Lenaxa Ltd | Construction | 2018 |
| Lens Trends UK Ltd | Manufacturing | 2022 |
| Lente Designs Limited | Other services | 2013 |
| Leonara Homes Private Limited | Real estate | 2024 |
| Leonardo Transport Ltd | Transport & logistics | 2015 |
| Leonclay Limited | Health & social care | 2020 |
| Leones Events Limited | Hospitality | 2025 |
| Leongreen Limited | Construction | 1996 |
| LES Liney Motor Repairs Ltd | Wholesale & retail | 2020 |
| Letcombe Bowers Developments Limited | Construction | 2016 |
| Letifos Ltd | Real estate | 2016 |
| Letz Property Services Limited | Administrative & support | 2012 |
| Levant Music Ltd | Information & communication | 2026 |
| Levee Consulting Ltd | Professional & scientific | 2019 |
| Level Event Limited | Arts & recreation | 2013 |
| Leverett Piano Holdings Ltd | Financial services | 2022 |
| Levick Design & Management Ltd | Construction | 2018 |
| Levin Solutions Ltd | Information & communication | 2010 |
| Levitate Construction Limited | Construction | 2004 |
| LEX Finishing Ltd | Construction | 2019 |
| LEX Legal Advice & Solution Ltd | Professional & scientific | 2025 |
| Leya Construction Limited | Construction | 2023 |
| Leye Consultants Limited | Information & communication | 2024 |
| Leys Surveying Ltd | Professional & scientific | 2003 |
| LFR Property Ltd | Real estate | 2026 |
| LG4 Payroll and Accounting Limited | Professional & scientific | 2019 |
| LGA Group Ltd | Construction | 2019 |
| LH2 Europe Advisory Ltd | Professional & scientific | 2021 |
| LHG (Little Goss Heath) Ltd | Professional & scientific | 2025 |
| LHL18 Properties Ltd | Real estate | 2026 |
| Libbyandalice Limited | Wholesale & retail | 2026 |
| Libitum Limited | Administrative & support | 2018 |
| Libra Homes (Aylesbury) Ltd | Real estate | 2021 |
| Libre Services Ltd | Information & communication | 2016 |
| Licensed Limited | Professional & scientific | 2024 |
| Lichfield House Limited | Real estate | 2009 |
| Lider Building Services Ltd | Construction | 2023 |
| Life Chiropractic Limited | Health & social care | 2025 |
| Lifeforth Ltd | Health & social care | 2025 |
| Lifeline Connect Ltd | Administrative & support | 2026 |
| Lifestyle Building Services Limited | Construction | 2019 |
| Lifestyle Eco Lodges Europe Limited | Construction | 2024 |
| Lifestyle Physiques Ltd | Other services | 2026 |
| Lifestyle Wealth Limited | Professional & scientific | 2023 |
| Liftique Technologies Ltd | Wholesale & retail | 2025 |
| Ligaoptions Ltd | Education | 2023 |
| Lightbulb Business Solutions Ltd | Financial services | 2011 |
| Lightech Limited | Construction | 2021 |
| Lightfoot Media Productions Ltd | Information & communication | 2005 |
| Lighthouse Childcare Consortium Ltd | Professional & scientific | 2020 |
| Lighthouse Safeguarding Ltd | Professional & scientific | 2023 |
| Lilin Ltd | Wholesale & retail | 2023 |