| Leapspin Limited | Real estate | 1986 |
| Learn Holistics Ltd | Health & social care | 2022 |
| LEARN2PASS Limited | Education | 2021 |
| Learnerbee Ltd | Education | 2022 |
| Learning for Enterprise Limited | Administrative & support | 2000 |
| Learning With an Electronic Brain Ltd | Education | 2026 |
| Lebre Limited | Professional & scientific | 2022 |
| Lebre Xana Ltd | Financial services | 2022 |
| Lecce Limited | Wholesale & retail | 2021 |
| Lecki Limited | Transport & logistics | 2016 |
| Lednl Holdings Limited | Financial services | 2026 |
| LEE Brown Studio Limited | Manufacturing | 2019 |
| LEE Empire Limited | Transport & logistics | 2022 |
| LEE Farm Potatoes Limited | Agriculture & fishing | 2026 |
| LEE Garth Tools Holdings Limited | Financial services | 2007 |
| LEE Hardcastle Consultancy Limited | Professional & scientific | 2026 |
| LEE Holmes & Sons Limited | Wholesale & retail | 2021 |
| LEE Johnson Rail Solutions Ltd | Construction | 2019 |
| Lee's Auto's Limited | Wholesale & retail | 2007 |
| Lee's Auto's Northern Limited | Wholesale & retail | 2019 |
| Lee's Plumbing & Heating Services Ltd | Construction | 2014 |
| Lee-Langford Estates Ltd | Real estate | 2025 |
| Leeds Furniture Company Limited | Wholesale & retail | 2022 |
| Leeloves 2 Care Limited | Health & social care | 2022 |
| Lees Group Enterprises Ltd | Construction | 2026 |
| Leese Services Ltd | Manufacturing | 2008 |
| Lega Tile UK Ltd | Construction | 2024 |
| Legacy Estate Homes Ltd | Hospitality | 2025 |
| Legacy Network | Other services | 2003 |
| Legacy Realty Ltd. | Real estate | 2023 |
| Legend Leathers Limited | Wholesale & retail | 2018 |
| Legend Pizza (Doncaster) Limited | Hospitality | 2023 |
| Legends Security Ltd | Administrative & support | 2018 |
| Legends Snooker Academy Ltd | Arts & recreation | 2025 |
| Leger Construction Ltd | Construction | 2019 |
| Leger Consultancy Group Ltd | Real estate | 2024 |
| Leger Education Trust | Education | 2011 |
| Leger Electrical Services Ltd | Manufacturing | 2014 |
| Leger Healthcare Ltd | Health & social care | 2016 |
| Leger Properties Limited | Real estate | 2003 |
| Leger Site Services Ltd | Construction | 2024 |
| Leger Therapy Services Limited | Health & social care | 2012 |
| Leggott Farming Limited | Agriculture & fishing | 2008 |
| Leggott Investments Limited | Real estate | 2015 |
| Leggott Ltd | Real estate | 2020 |
| Leia and Friends Dog Boarding Ltd | Agriculture & fishing | 2025 |
| Leigh Wilson Plumbing & GAS Limited | Construction | 2010 |
| Leighside Limited | Extraterritorial | 2012 |
| Leisure Vehicles Limited | Wholesale & retail | 2023 |
| Lemonbridge Collective Ltd | Extraterritorial | 2026 |
| LEN Hamer Ltd | Wholesale & retail | 2024 |
| Lena Express Ltd | Hospitality | 2026 |
| Leneil Developments Limited | Real estate | 2025 |
| Lennard Business Services Ltd | Administrative & support | 2025 |
| Lens and Layers Ltd | Hospitality | 2025 |
| Lenscafraluc Limited | Real estate | 2019 |
| Lense Technology Systems Ltd | Information & communication | 2025 |
| Lensgo Limited | Professional & scientific | 2018 |
| Lentus Opus LLP | | 2019 |
| LEO INT Limited | Real estate | 2025 |
| Leodis Kitchen Ltd | Hospitality | 2020 |
| Leoex Logistics Ltd | Transport & logistics | 2019 |
| Leon Motor Services,Limited | Information & communication | 1946 |
| Leon Pizza Limited | Hospitality | 2025 |
| Leon Silver Limited | Arts & recreation | 2014 |
| Leona Cuffy Holdings Ltd | Other services | 2024 |
| Leonard Delivery Ltd | Transport & logistics | 2026 |
| Leonard Tomlinson Limited | Wholesale & retail | 1958 |
| Leonard Wright Developments Ltd | Construction | 2015 |
| LES Salles Limited | Real estate | 2020 |
| Lesley Blackett HR Consultant Limited | Administrative & support | 2019 |
| Leszek Klimanski Ltd | Transport & logistics | 2014 |
| LET the Children Live! | Hospitality | 2010 |
| LET US Find IT Limited | Wholesale & retail | 2015 |
| LETS2GO Ltd | Real estate | 2016 |
| Letwell Commercial Ltd | Administrative & support | 2017 |
| Leung & Sons Limited | Real estate | 2026 |
| LEV Transport Ltd | Transport & logistics | 2023 |
| Level 27 Limited | Professional & scientific | 2019 |
| Level UP Assessments Ltd | Construction | 2025 |
| Levelark Ltd | Professional & scientific | 2025 |
| Leverton Property Services Limited | Real estate | 2017 |
| Levi & Co. FP Ltd | Transport & logistics | 2025 |
| Levll-Upp Ltd | Professional & scientific | 2023 |
| Lewcomm Ltd | Information & communication | 2017 |
| Lewes Estates Land and New Homes Ltd | Real estate | 2019 |
| Lewes House Sale.Com Limited | Administrative & support | 2017 |
| Lewin Hall Limited | Administrative & support | 2009 |
| Lewis Brothers Electrical Limited | Construction | 2025 |
| Lewis Morgan Creative Timber Limited | Construction | 2004 |
| Lewis Oliver Electrical Limited | Construction | 2017 |
| Lewis Rhodes Holdings Limited | Professional & scientific | 2009 |
| Lewis Taylor TM Ltd | Construction | 2023 |
| Lewis's Holdings Ltd | Real estate | 2016 |
| Lewis's Ltd | Professional & scientific | 2005 |
| Lewithèa Ltd | Construction | 2024 |
| Lewken Plumbing and Heating Ltd | Construction | 2022 |
| LEX Hygiene Ltd | Water & waste | 2016 |
| Lexquire LLP | | 2017 |
| Leylam Pizza Limited | Hospitality | 2025 |