| Lister Shearing Equipment Limited | Manufacturing | 1998 |
| Lister Shearing Limited | Professional & scientific | 1945 |
| Litchfield Trading Limited | Agriculture & fishing | 2024 |
| Litmus Technology Limited | Information & communication | 2023 |
| Little Blue Private Jets Limited | Transport & logistics | 2010 |
| Little Bunnies Sleep Consultant Limited | Health & social care | 2023 |
| Little Explorers Nursery and Preschool Limited | Education | 2012 |
| Little Gems and Little Treasures Ltd | Administrative & support | 2003 |
| Little Hendom Farm Limited | Hospitality | 2025 |
| Little Hoots Limited | Education | 2008 |
| Little Ireley Stud LLP | | 2019 |
| Little JET Management Limited | Transport & logistics | 2023 |
| Little Lambs (Longlevens) Limited | Health & social care | 2022 |
| Little Moments Group Ltd | Professional & scientific | 2019 |
| Little Monsters Rugby Limited | Education | 2016 |
| Little Paddocks (UK) Limited | Administrative & support | 2012 |
| Little Paradise Ltd | Other services | 2020 |
| Little Pembury Management Company Limited | Households | 1983 |
| Little Smarties Limited | Education | 2016 |
| Little Spark Strategy Ltd | Professional & scientific | 2025 |
| Little Star Sailor Ltd | Information & communication | 2021 |
| Little Steps (Dunstable) Limited | Health & social care | 2026 |
| Little Stone, Big Rock Ltd | Real estate | 2021 |
| Little Tigers Ltd | Education | 2009 |
| Little Tyke Ltd | Real estate | 2016 |
| Little Way Catholic Educational Trust | Education | 2023 |
| Little Woodlands Day Nursery Limited | Health & social care | 2025 |
| Littleworth Developments Limited | Real estate | 2025 |
| Liutkus Medical Services Limited | Health & social care | 2022 |
| Live Better CBD Ltd | Wholesale & retail | 2018 |
| Live in Care 24 Ltd | Health & social care | 2017 |
| Live, Love, Learn, Lead Ltd | Other services | 2024 |
| Lived Experience Inspires Ltd | Education | 2026 |
| Livenit Limited | Wholesale & retail | 2025 |
| Livestock Genetics (Publishers) Limited | Information & communication | 2019 |
| Living the Cornish Dream Limited | Real estate | 2023 |
| Livorno Digital Ltd | Professional & scientific | 2025 |
| LIZ Rose Interiors Ltd | Professional & scientific | 2019 |
| LJ Bridal Collection Ltd | Wholesale & retail | 2019 |
| Ljai Ltd | Information & communication | 2026 |
| LJK Onefifty Ltd | Arts & recreation | 2021 |
| LJR Consultancy Luxury Hotels and Resorts Ltd | Administrative & support | 2020 |
| LJT Inventories Limited | Real estate | 2016 |
| LJW Permanent Cosmetics Limited | Other services | 2017 |
| LK Flooring Cheltenham Limited | Manufacturing | 2012 |
| LKC UK Limited | Professional & scientific | 2008 |
| LKS Management Consultancy Ltd | Professional & scientific | 2018 |
| LKS Partners LLP | | 2025 |
| Llandow Trading Estate Limited | Other services | 2003 |
| Llangrove Ltd | Construction | 2022 |
| Lloyd Family Investment Group Limited | Real estate | 2025 |
| Lloyd Looms Furniture Company Ltd | Wholesale & retail | 2019 |
| LLW Group Ltd | Other services | 2020 |
| Llwyndyrus Solar Farm Limited | Energy | 2015 |
| LM Carpe Diem Property Limited | Real estate | 2011 |
| LM Tree Care Limited | Administrative & support | 2022 |
| LMA2 Limited | Extraterritorial | 2015 |
| Lmcl Limited | Information & communication | 2025 |
| LMH Partners Limited | Professional & scientific | 2021 |
| LMS Global (UK) Ltd | Information & communication | 2003 |
| LMS Management Services Ltd | Financial services | 2025 |
| Lnbs Investment UK | Financial services | 2021 |
| Lnbs Investment US | Financial services | 2021 |
| LNO Estates Ltd | Real estate | 2024 |
| LNO Grooming Ltd | Other services | 2025 |
| LNO Jewellery Ltd | Wholesale & retail | 2021 |
| Loamsdown Limited | Professional & scientific | 2012 |
| Loancompare.Ai Ltd | Financial services | 2024 |
| LOAP2022 Ltd. | Professional & scientific | 2018 |
| Local Retail Limited | Wholesale & retail | 2024 |
| Local Tax Accountants Limited | Professional & scientific | 2013 |
| Lockslea Ltd | Financial services | 2026 |
| Locus Robotics U.K. Ltd | Administrative & support | 2023 |
| Lodestone Technology Ltd | Professional & scientific | 2024 |
| Loft Furniture Limited | Wholesale & retail | 2010 |
| Logging-In Limited | Information & communication | 2021 |
| Logical Living Limited | Construction | 2004 |
| Logictiles Ltd | Information & communication | 2024 |
| LOK Oxprop 1 Ltd | Real estate | 2025 |
| Lokaz Limited | Professional & scientific | 2005 |
| Lokhon Living Limited | Construction | 2023 |
| Lola and Blake Ltd | Wholesale & retail | 2019 |
| Lomond Anaesthetics Limited | Health & social care | 2023 |
| London Brand Limited | Construction | 2018 |
| London Broil Bagshop Ltd | Manufacturing | 2019 |
| London City Access Limited | Construction | 2017 |
| London City Media Limited | Information & communication | 2011 |
| London Look Hairdresser Ltd | Other services | 2025 |
| London Road (Cheltenham) Management Company Limited | Households | 1990 |
| London Road Tetbury Limited | Real estate | 2021 |
| Lone FOX Ltd | Arts & recreation | 2021 |
| Lone Wolf Management Limited | Administrative & support | 2012 |
| Long ASH Services Limited | Professional & scientific | 2012 |
| Long Hard Look Limited | Hospitality | 2022 |
| Longcroft Building Services Limited | Construction | 2000 |
| Longcross Transport Limited | Other services | 2010 |
| Longevity Health Holdings Ltd | Health & social care | 2026 |
| Longford Court Residential Management Company Limited | Households | 1996 |
| Longhill Developements Ltd | Construction | 2022 |
| Longwood School and Nursery Limited | Education | 2016 |