| LEE Pennington Ltd | Information & communication | 2022 |
| LEE Rayson Limited | Construction | 2017 |
| LEE Thompson Developments Ltd | Manufacturing | 2024 |
| Leepz Limited | Hospitality | 2025 |
| Lees Lettings Limited | Construction | 2017 |
| Legacy Meridian Limited | Information & communication | 2025 |
| Legacymemoria Ltd | Wholesale & retail | 2026 |
| Legal IQ Ltd | Professional & scientific | 2023 |
| Legge Solutions Ltd | Other services | 2010 |
| Leggett Group Limited | Wholesale & retail | 2021 |
| Legna Limited | Manufacturing | 2024 |
| Leisure Professionals Limited | Administrative & support | 2014 |
| Leisure Sales Limited | Arts & recreation | 2013 |
| Lekaro Services Ltd | Administrative & support | 2014 |
| LEL Mechanical Services Ltd | Manufacturing | 2026 |
| Lelys Renovations Limited | Construction | 2024 |
| Lema Leads Limited | Administrative & support | 2022 |
| Lemonbox Ltd | Hospitality | 2024 |
| Lenny's Prints Ltd | Manufacturing | 2020 |
| Lenuta Romanian Traditional Food Ltd | Hospitality | 2023 |
| LEO Car Company Limited | Wholesale & retail | 2003 |
| Leon Lettings Limited | Real estate | 2018 |
| Leonard BYE Limited | Professional & scientific | 2014 |
| Leporis Hotels & Tours Ltd | Hospitality | 2023 |
| Lerclr Trading Ltd | Wholesale & retail | 2025 |
| LES Harker Bars & Pubs Ltd | Hospitality | 2026 |
| LES Woolston Haulage Limited | Transport & logistics | 2001 |
| Lesa Engineering Limited | Construction | 2017 |
| Lesa Estates Ltd | Real estate | 2021 |
| Lesa Property Management Ltd | Real estate | 2025 |
| LET Select Property Limited | Real estate | 2020 |
| Lets Run Adventures Ltd | Arts & recreation | 2018 |
| Letsavvy Ltd | Real estate | 2025 |
| Lettings Express UK Limited | Real estate | 2017 |
| LETTINGS365(UK) Ltd | Real estate | 2024 |
| Leven Sourcing Ltd | Wholesale & retail | 2026 |
| Lewis Llewellyn Logistics Ltd | Transport & logistics | 2025 |
| Lexsk Legal Limited | Professional & scientific | 2025 |
| Lezzets Restaurant Limited | Hospitality | 2023 |
| LFC (NE) Ltd | Hospitality | 2025 |
| LG Caravans Ltd | Wholesale & retail | 2023 |
| LG Contracts Ltd | Construction | 2023 |
| LG Engineering Group Ltd | Professional & scientific | 2024 |
| LG Maritime (UK) Limited | Professional & scientific | 2023 |
| LG Maritime Limited | Professional & scientific | 2008 |
| LG Parking Ltd | Transport & logistics | 2018 |
| LGC Training and Consultancy Limited | Other services | 2017 |
| Lglf Ltd | Professional & scientific | 2022 |
| Lgqs Limited | Administrative & support | 2016 |
| LH Fabrication Services Ltd | Manufacturing | 2010 |
| LH Pallets Ltd | Administrative & support | 2024 |
| LH Scaffolding Services Ltd | Construction | 2019 |
| LH Turcan Logistics Limited | Transport & logistics | 2025 |
| Lhews Fabrications Ltd | Manufacturing | 2019 |
| Liam Morrison Ltd | Construction | 2022 |
| Liam's Jointing Services Ltd | Construction | 2023 |
| Liamar Limited | Wholesale & retail | 2026 |
| Lianhetech Europe Limited | Financial services | 2017 |
| Lianhetech Holdco Limited | Financial services | 2017 |
| Libellum Asset Integrity Management Ltd | Professional & scientific | 2018 |
| Libellum Holdings Limited | Professional & scientific | 2025 |
| Libellum Quality Solutions Ltd | Professional & scientific | 2025 |
| Libellum Testing & Inspection Ltd | Professional & scientific | 2025 |
| Liberty Design Ltd | Professional & scientific | 2011 |
| Liberty Maritime Ltd | Transport & logistics | 2024 |
| Libra Joinery Ltd | Construction | 2026 |
| Liddle by Liddle Offshore Services Ltd | Construction | 2026 |
| Lidgett Estimating Service Limited | Professional & scientific | 2020 |
| Life Ninja Education Ltd | Information & communication | 2019 |
| Life People Business Limited | Professional & scientific | 2023 |
| Lifeaid Plus Healthcare Ltd | Health & social care | 2022 |
| Lift by LIB Ltd | Other services | 2025 |
| Liftpower Limited | Manufacturing | 2020 |
| Light Cuts (NE) Limited | Other services | 2023 |
| Light Engineering Ltd | Professional & scientific | 2025 |
| LIH Safety Solutions Ltd | Public administration | 2023 |
| Liip Limited | Professional & scientific | 2017 |
| LIK Services Ltd | Information & communication | 2025 |
| Lilatcho Ltd | Manufacturing | 2022 |
| Lilly Bear Stephens Ltd | Wholesale & retail | 2026 |
| Lilly Site Services Ltd | Administrative & support | 2023 |
| Lilly Tasty Eats Ltd | Hospitality | 2024 |
| Lily Maggie Occasion Wear Limited | Wholesale & retail | 2016 |
| Limatech Ltd | Wholesale & retail | 2018 |
| Lime Contracting Ltd | Manufacturing | 2023 |
| Limetree Student Living Ltd | Real estate | 2016 |
| Linby Engineering Limited | Information & communication | 2019 |
| Linecraft Studio Ltd | Professional & scientific | 2026 |
| Lineside Groundworks Ltd | Construction | 2020 |
| Lingerie Doll Limited | Wholesale & retail | 2023 |
| Link Project CIC | Information & communication | 2021 |
| Linthorpe Bars Limited | Hospitality | 2024 |
| Linthorpe Evolution Limited | Arts & recreation | 2017 |
| Linthorpe Furnishing (North East) Ltd | Wholesale & retail | 2026 |
| Linthorpe Furnishings Ltd | Wholesale & retail | 2014 |
| Linthorpe Restaurant Limited | Hospitality | 2025 |
| Linthorpe Tanning Limited | Other services | 2026 |
| Linthorpeelectrical Ltd | Construction | 2021 |
| Linton 9 Limited | Extraterritorial | 2014 |
| Lion House Dental Practice Limited | Health & social care | 2012 |