| LD Finance Limited | Professional & scientific | 2019 |
| LD Training Solutions Limited | Education | 2022 |
| LE Surfaces UK Co., Ltd | Manufacturing | 2024 |
| LEA Services (West Midlands) Limited | Manufacturing | 2008 |
| Leacy UK Limited | Wholesale & retail | 2024 |
| Lead Edge Ltd | Education | 2009 |
| Leader Executive Search Limited | Administrative & support | 2011 |
| LEADING360 Limited | Information & communication | 2021 |
| Leafdale Ltd | Real estate | 1989 |
| LEARN2FILM Ltd | Education | 2025 |
| Lease & Business Finance Ltd | Financial services | 1997 |
| Leaving Work Behind Limited | Information & communication | 2015 |
| Ledgeriq Advisory Ltd | Professional & scientific | 2026 |
| Leesham Properties C.I.C. | Hospitality | 2023 |
| Legacy by SIM Ltd | Wholesale & retail | 2022 |
| Legacy Heating Services Limited | Construction | 2021 |
| Legacy of Love Limited | Wholesale & retail | 2025 |
| Lenches Bridge Commercials Limited | Professional & scientific | 1991 |
| LEO Fittings Limited | Wholesale & retail | 1984 |
| Leobrooks Limited | Information & communication | 2018 |
| Leona Estates Limited | Real estate | 2022 |
| Leonard's Garage Limited | Real estate | 1957 |
| Leonards of New Milton Limited | Administrative & support | 1978 |
| LES Williams Builders Limited | Construction | 2004 |
| Lesson Pro Limited | Information & communication | 2020 |
| Letmack Ltd | Health & social care | 2015 |
| Lettravane Limited | Manufacturing | 1973 |
| Level Line Consulting Ltd | Professional & scientific | 2025 |
| Lguk Property Limited | Real estate | 2021 |
| LHG Associates Ltd | Professional & scientific | 2018 |
| Li-Bonket Limited | Real estate | 2023 |
| Liam Pitchford Design Ltd | Professional & scientific | 2023 |
| Liam Walker Limited | Other services | 2007 |
| Lianne LEE Financial Planning Ltd | Professional & scientific | 2023 |
| Lifestyle Environmental Ltd | Construction | 2013 |
| Lifestyle Rooms Ltd | Real estate | 2017 |
| Lighthouse Design and Build Limited | Administrative & support | 2008 |
| Lighthouse Kitchen Service Ltd | Hospitality | 2025 |
| Lightsure Solar Ltd | Manufacturing | 2019 |
| Lily Grace Keepsakes Ltd | Manufacturing | 2018 |
| Linaker Green Limited | Financial services | 1987 |
| Linea Electrical Services Ltd | Construction | 2020 |
| Linkcare Limited | Wholesale & retail | 1992 |
| Links Analysis Ltd | Information & communication | 2024 |
| Links Rich Limited | Real estate | 2016 |
| Linx Contracting Ltd | Construction | 2025 |
| Lions DEN Investment Ltd | Real estate | 2024 |
| Lipotrimz 3D Limited | Other services | 2013 |
| Liscarret Properties Limited | Construction | 2009 |
| Litherland Photography Ltd | Professional & scientific | 2023 |
| Litose Group Limited | Financial services | 2020 |
| Little Brookend Farm Limited | Professional & scientific | 2004 |
| Little Roo’S Soft Play Ltd | Arts & recreation | 2026 |
| Littleash Limited | Professional & scientific | 2024 |
| Littlechophouse Limited | Hospitality | 2025 |
| Littleshire Limited | Extraterritorial | 1979 |
| Live Creakin Holdings Limited | Real estate | 2024 |
| Live Creakin Limited | Real estate | 2000 |
| Live in Luxury Ltd | Real estate | 2022 |
| Live IT Love IT Sell IT Ltd | Administrative & support | 2017 |
| Living Design & Build Limited | Construction | 2008 |
| LIZ Hartley Limited | Administrative & support | 2007 |
| Lizzy's Ironing and Laundry Services Limited | Other services | 2026 |
| LJB Accountancy Limited | Professional & scientific | 2018 |
| LJD Meats Ltd | Wholesale & retail | 2026 |
| Ljmm Services Ltd | Professional & scientific | 2025 |
| LK Services and Maintenance Ltd | Construction | 2026 |
| Llachar Limited | Real estate | 2022 |
| Lm&P Ltd | Wholesale & retail | 2022 |
| Lodgefield Motors Ltd | Wholesale & retail | 2022 |
| Logan K Developments Limited | Construction | 2016 |
| Logfreight Limited | Extraterritorial | 2011 |
| Logistic Engineering Services Ltd | Administrative & support | 2008 |
| Lokasher & Co. Limited | Wholesale & retail | 2026 |
| London Clinical and Legal Limited | Health & social care | 2013 |
| London Medical Legal Limited | Professional & scientific | 2026 |
| London Screw Co.Limited | Manufacturing | 1929 |
| Long Jade Limited | Hospitality | 2026 |
| Long Lane Barber Ltd | Other services | 2025 |
| Longhurst Communications (Holdings) Limited | Professional & scientific | 2010 |
| Longhurst Communications Limited | Professional & scientific | 2001 |
| Longworth Holdings Ltd | Administrative & support | 2005 |
| Longworth Property Developments Ltd | Construction | 2024 |
| Looocccyyydoodle Ltd | Construction | 2024 |
| Lord Telford Limited | Construction | 2025 |
| Lotus Flower Enterprises Limited | Real estate | 2025 |
| Louis Bella Holdings Limited | Professional & scientific | 2016 |
| Lounge 101 Limited | Hospitality | 2017 |
| Loungeabout Bar Ltd | Hospitality | 2021 |
| Love Scaffolding Ltd | Construction | 2022 |
| Lovetree Design Limited | Wholesale & retail | 2015 |
| LOW Leam Investment Company Limited | Financial services | 2018 |
| LPP Design Limited | Professional & scientific | 2005 |
| Lqnb Limited | Hospitality | 2019 |
| LR & P Consultants Ltd | Construction | 2019 |
| LR Arabian OUD Fragrances Limited | Wholesale & retail | 2025 |
| LR Electrical Contracting Limited | Construction | 2025 |
| LR Speedy Couriers Limited | Transport & logistics | 2026 |
| LRS Property Group Limited | Construction | 2016 |
| LSC Lifestyle Limited | Wholesale & retail | 2021 |