| Kilbride Group Ltd | Financial services | 2023 |
| Kilbride Roofing Ltd | Construction | 2007 |
| Killard Homes Limited | Real estate | 2015 |
| Kilnwood Open Space Management Company Limited | Households | 2015 |
| Kingdom's Tours Limited | Transport & logistics | 1961 |
| Kingman Property Law Limited | Professional & scientific | 2025 |
| Kingsmark Products Ltd | Wholesale & retail | 2020 |
| Kingston Building Contractors Limited | Construction | 2002 |
| Kingston Holding Group Limited | Professional & scientific | 2016 |
| Kingston Property Limited | Construction | 2008 |
| Kins Razor Ltd | Other services | 2025 |
| Kirkland Property Limited | Real estate | 2026 |
| Kislingbury Property Consultants Ltd | Professional & scientific | 2016 |
| Kiwi Express Ltd | Agriculture & fishing | 2024 |
| KL Farming Services Ltd | Agriculture & fishing | 2025 |
| Knight Dagger Ltd | Information & communication | 2011 |
| Knight's Coffee Bar and Grill Ltd | Hospitality | 2025 |
| Knightshayes Estate Energy Ltd | Energy | 2011 |
| Knightshayes Estate Products Limited | Hospitality | 1943 |
| Kovka Decor Limited | Manufacturing | 2023 |
| KRE8TIVE Services Ltd | Health & social care | 2019 |
| Kristiyan’S Balkan Market Ltd | Wholesale & retail | 2025 |
| KS Electrical Solutions Ltd | Construction | 2015 |
| KSB Ground Engineering Ltd | Construction | 2025 |
| KSP Foods Ltd | Wholesale & retail | 2023 |
| Ktng Ltd | Real estate | 2024 |
| Kurdistan Society Ltd | Administrative & support | 2026 |
| Kyann Wellbeing Limited | Information & communication | 2025 |
| Känna Limited | Wholesale & retail | 2024 |
| L & A.T Design Limited | Construction | 2024 |
| L J Heywood Limited | Agriculture & fishing | 2010 |
| L J O'Cathail Ltd | Real estate | 2018 |
| LA Cure UK Limited | Wholesale & retail | 2001 |
| LA Petite Madeleine Limited | Hospitality | 2011 |
| Ladywell Meadows Management Company Limited | Households | 2016 |
| Lamiea Ltd | Extraterritorial | 2017 |
| Lamorran Holdings Ltd | Real estate | 2025 |
| Lanacre Management Services Limited | Professional & scientific | 1997 |
| Landman LLP | | 2004 |
| Landman Property Consultants Ltd | Professional & scientific | 2008 |
| Langdown Developments Limited | Construction | 2020 |
| Langdown Management Company Ltd | Real estate | 2021 |
| Lantern Library C.I.C. | Education | 2026 |
| Lantern Life Ltd | Administrative & support | 2020 |
| Larimos UK Ltd | Hospitality | 2024 |
| Laser Labs Games CIC | Information & communication | 2016 |
| Last Leaf LLP | | 2017 |
| Lathwell Strategic Ltd | Professional & scientific | 2021 |
| Laura Stoddart Ltd | Wholesale & retail | 2015 |
| Lawday Construction Limited | Construction | 2025 |
| Layaa Limited | Wholesale & retail | 2023 |
| LCJ Builders and Stonemason Limited | Construction | 2023 |
| Lean and Bond Limited | Real estate | 2024 |
| Leandro Silva Plumbing Limited | Construction | 2017 |
| Leannie Properties Ltd | Real estate | 2022 |
| Leckhampton Legacy Limited | Real estate | 2024 |
| LEE DEV Ltd | Information & communication | 2014 |
| Legacy Imprint SW Ltd | Wholesale & retail | 2026 |
| Leighton-Boyce Properties Ltd. | Administrative & support | 1999 |
| Leisure MAX Ltd | Wholesale & retail | 2018 |
| Lemur Electrical Limited | Construction | 2024 |
| Leon Holly Racing 87 Limited | Arts & recreation | 2024 |
| Levick Holding Ltd | Hospitality | 2020 |
| LH Bespoke Plastic Fabrications Ltd | Manufacturing | 2025 |
| LHG Property Group Ltd | Real estate | 2024 |
| Life and Wellness Psychiatry Limited | Health & social care | 2023 |
| Lighthouse SW Ltd | Real estate | 2018 |
| Lily Faith Ltd | Arts & recreation | 2024 |
| Lion Pest Control Ltd | Agriculture & fishing | 2021 |
| Lithocarp Investments Ltd | Financial services | 2025 |
| Little Cotton Farm (Dartmouth) Management Company Ltd | Households | 2020 |
| Little Profs Ltd | Wholesale & retail | 2020 |
| Live Reef Distribution Limited | Manufacturing | 2016 |
| Live Reef Limited | Agriculture & fishing | 2014 |
| LJK Global Limited | Administrative & support | 2018 |
| Loam SW Ltd | Professional & scientific | 2026 |
| Local Weather Ltd | Professional & scientific | 2025 |
| Locksmiths & Security Ltd | Construction | 2023 |
| Lockwood Farms Limited | Agriculture & fishing | 2017 |
| LOCO2 Heat Limited | Wholesale & retail | 2013 |
| Loftus Plastering & Rendering Ltd | Construction | 2022 |
| Logos Books Ltd | Education | 2026 |
| Lohydrogen Limited | Professional & scientific | 2014 |
| Lola Care (SW) Ltd | Health & social care | 2019 |
| Lola Collection Ltd | Wholesale & retail | 2019 |
| London & Devonshire Trust Limited | Real estate | 1984 |
| London Cider Company Ltd | Manufacturing | 2013 |
| Longhouse Ltd | Professional & scientific | 2012 |
| Longston Cross Open Space Management Company Limited | Households | 2020 |
| Louellen Engineering Ltd | Construction | 2013 |
| Lovitt Ltd | Construction | 2015 |
| Lower Warnicombe Court Limited | Households | 1999 |
| Lowman Manufacturing Company Limited | Financial services | 1984 |
| Loxbeare Barns Company Ltd | Households | 2010 |
| Loyton Estates Management Limited | Real estate | 2017 |
| LRG Fitness Limited | Professional & scientific | 2016 |
| LRS Haulage Ltd | Transport & logistics | 2018 |
| Lsmb Ltd | Other services | 2020 |
| Ludo & Partners HR Ltd | Professional & scientific | 2023 |
| Luffman Engineering Limited | Manufacturing | 2002 |