| Kyroc Ltd | Information & communication | 2019 |
| L a Lording Productions Limited | Information & communication | 2025 |
| L Agence Limited | Professional & scientific | 1988 |
| L Burnham Ltd | Professional & scientific | 2017 |
| L H Houses Ltd | Real estate | 2025 |
| L Harvey & SON Group Limited | Financial services | 2017 |
| L I Specialists Ltd | Administrative & support | 2023 |
| L M Engineering Consultants Limited | Professional & scientific | 2001 |
| L T Saunders Construction Ltd | Construction | 2025 |
| L W Butler & Co Limited | Manufacturing | 2006 |
| L Wood Properties Ltd | Real estate | 2021 |
| L&D Ventures Ltd | Real estate | 2020 |
| L&N Building Services Ltd | Construction | 2024 |
| L&S Waste Management Limited | Water & waste | 1997 |
| L'Amour Clinic Ltd | Health & social care | 2019 |
| L. Harvey & SON Limited | Construction | 1964 |
| L.& A.Freeman Limited | Extraterritorial | 1958 |
| L.& T.Developments Limited | Construction | 1960 |
| L2I Ltd | Manufacturing | 2006 |
| L2I Managements Limited | Professional & scientific | 2013 |
| L2L Ltd | Hospitality | 2019 |
| L3LOSSOM Limited | Other services | 2020 |
| LA Bottega FA Ltd | Wholesale & retail | 2022 |
| LA Creative Content Limited | Information & communication | 2022 |
| LA Playa Global Limited | Extraterritorial | 2025 |
| LA Playa Limited | Extraterritorial | 2025 |
| LA Unguru Ltd | Hospitality | 2025 |
| LA VIA Trading Limited | Wholesale & retail | 2016 |
| LA VIE Nail Lounge Ltd | Other services | 2026 |
| LA VIE Nutrition Ltd | Professional & scientific | 2015 |
| Label TIA Ltd | Wholesale & retail | 2019 |
| Labour for Trans Rights Ltd | Other services | 2022 |
| Labvantage Systems Holding Limited | Financial services | 2024 |
| Labvantage Systems Ltd | Financial services | 2022 |
| Lachlan Smith Films Ltd | Information & communication | 2020 |
| Lady Lane Freehold Limited | Households | 2020 |
| Lady Lisa Lashes Limited | Wholesale & retail | 2025 |
| Lagoon Enterprises Limited | Administrative & support | 2003 |
| Lahnsohn Arbor Limited | Professional & scientific | 1980 |
| Laing Homes Limited | Extraterritorial | 1953 |
| Laing Land Limited | Extraterritorial | 1956 |
| Lakeside Bathrooms Limited | Construction | 2004 |
| Lakeside Equities Limited | Real estate | 2020 |
| Lakeside Software Emea Limited | Information & communication | 2012 |
| Lakewood Services Ltd | Administrative & support | 2023 |
| Lally Lettings London Ltd | Real estate | 2024 |
| Lallypops FX Limited | Information & communication | 2023 |
| LAM Investment Holdings Ltd | Administrative & support | 2020 |
| Lamaca Consulting Ltd | Information & communication | 2025 |
| Lambourn Coach Builders Limited | | 1978 |
| Lambs in a Field of Scissors Ltd | Information & communication | 2025 |
| Lamps on Line Limited | Wholesale & retail | 2006 |
| Lana's Legacy Ltd | Professional & scientific | 2025 |
| Landor Design Limited | Professional & scientific | 1992 |
| Landspace Global Ltd | Real estate | 2016 |
| Landtrust Developments Limited | Extraterritorial | 2007 |
| Langham and Gloucester Securities Limited | Real estate | 1987 |
| Langrove Holdings Ltd | Construction | 2025 |
| Lansdales Pharmacy Limited | Wholesale & retail | 1999 |
| Lantis Watch Company Ltd | Manufacturing | 2020 |
| Larbre Maintenance Property Services Limited | Construction | 2024 |
| Larbre Maintenance Services LLP | | 2014 |
| Larissann Limited | Health & social care | 2020 |
| Lark Engineering (IDS) Limited | Professional & scientific | 2021 |
| Larne Grove Ltd | Hospitality | 2026 |
| Larose Hair Ltd | Other services | 2024 |
| Lashology England Ltd | Other services | 2022 |
| Lathom Consulting Ltd | Professional & scientific | 2013 |
| Latimer House Management Company Limited | Households | 1992 |
| Latitude by Lats Limited | Professional & scientific | 2018 |
| Latouche Enterprises Limited | Wholesale & retail | 2021 |
| Launchultra Limited | Wholesale & retail | 1991 |
| Launderoo Ltd | Administrative & support | 2020 |
| Laur & Denysa Limited | Transport & logistics | 2015 |
| Laurajeanwelsh Limited | Information & communication | 2012 |
| Laurajeanwelsh Touring Ltd | Arts & recreation | 2013 |
| Lauren Brown Ltd | Education | 2022 |
| Lauren the Senco Ltd | Education | 2026 |
| Laurica Hire Ltd | Transport & logistics | 2024 |
| Lavelle & Sons Limited | Wholesale & retail | 1977 |
| Lavis Technology Limited | Professional & scientific | 2020 |
| Lavricks Ltd | Wholesale & retail | 2024 |
| Lavricks Property Holdings Ltd | Real estate | 2025 |
| Law Capital Limited | Financial services | 2021 |
| Lawefield Store Ltd | Wholesale & retail | 2024 |
| Lawful Contract Limited | Extraterritorial | 2018 |
| Lawrence Goodwin Ltd | Manufacturing | 2019 |
| Lawrence Hansen Ltd | Arts & recreation | 2018 |
| Lawrest Ltd | Construction | 2010 |
| Lawson & Sons Lettings and Sales Limited | Real estate | 2024 |
| Laxmi Consulting (UK) Ltd | Professional & scientific | 2013 |
| Laxmi Kitchen Limited | Hospitality | 2022 |
| Laynes Limited | Real estate | 2014 |
| Layton Air Conditioning Limited | Construction | 2025 |
| Lazor Construction Ltd | Construction | 2016 |
| LB Coachworks Ltd | Wholesale & retail | 2022 |
| LB Electrical Bucks Ltd | Construction | 2019 |
| LB Passive Fire Limited | Public administration | 2021 |
| LB Property&Compliance Solutions Ltd | Professional & scientific | 2023 |
| LC Print & Signs Limited | Manufacturing | 2019 |