| London Commercial Kitchens Ltd | Construction | 2025 |
| London Concierge Ride Limited | Transport & logistics | 2026 |
| London Hotel Holdings 2 Limited | Real estate | 2023 |
| London Hotel Holdings 3 Limited | Hospitality | 2025 |
| London Hotel Holdings 4 Limited | Hospitality | 2025 |
| London Hotel Holdings 5 Limited | Hospitality | 2025 |
| London Hotel Holdings Limited | Real estate | 2022 |
| London Private Capital Limited | Professional & scientific | 2000 |
| London Professional Windows Limited | Construction | 2015 |
| London Top Choice Ltd | Wholesale & retail | 2022 |
| London Weee Recycle Ltd | Water & waste | 2025 |
| London's Finest Cleaning Ltd | Administrative & support | 2019 |
| Long Meadow (Holdings) Limited | Financial services | 2014 |
| Long Meadow (Ripon) Limited | Health & social care | 1941 |
| Longacre Property Services Limited | Real estate | 2023 |
| Loomandrainage Ltd | Water & waste | 2020 |
| Loome Limited | Wholesale & retail | 2012 |
| Lorane Court RTM Company Limited | Households | 2017 |
| Lord of the Kebabs Ltd | Hospitality | 2025 |
| Lordd Limited | Wholesale & retail | 2020 |
| Lords Group Holdings Limited | Real estate | 1971 |
| Lorry Parks UK Ltd | Real estate | 2025 |
| Lotic Plumbing Solutions Limited | Construction | 2025 |
| Loulous Childcare Limited | Health & social care | 2023 |
| Love Gardens Ltd | Administrative & support | 2019 |
| Lovelock Effects Ltd | Manufacturing | 2024 |
| LPC Property Limited | Construction | 2017 |
| Lpepharma Limited | Professional & scientific | 2023 |
| LPS Construction and Decorating Ltd | Construction | 2023 |
| LR Printing Ltd | Wholesale & retail | 2017 |
| LRA Electrical Ltd | Construction | 2026 |
| LRF Trans Ltd | Transport & logistics | 2020 |
| LRK Construct Limited | Construction | 2026 |
| LS Adventure Co. Limited | Education | 2026 |
| LS Plant & Light Commercial Repairs Limited | Manufacturing | 2020 |
| LS Sandhu Transport Ltd | Transport & logistics | 2026 |
| LSB Carpentry Limited | Construction | 2011 |
| LSE Property Investments Limited | Real estate | 2017 |
| LSJ Finance Ltd | Professional & scientific | 2023 |
| LSK Hire Ltd | Other services | 2016 |
| LT Education Ltd | Education | 2015 |
| Ltex Ltd | Professional & scientific | 2025 |
| LTM Electrics Ltd | Construction | 2018 |
| Ltmr Switchgear Services Ltd | Manufacturing | 2026 |
| LU Investment Limited | Real estate | 2026 |
| LU6 Local Limited | Wholesale & retail | 2023 |
| Luah Consulting Limited | Construction | 2025 |
| Lucis Ltd | Construction | 2016 |
| Lucky Corner Ltd | Hospitality | 2026 |
| Lucky Uncle Gourmet Ltd | Hospitality | 2023 |
| Lucky Victims Music Ltd | Manufacturing | 2014 |
| Luckystar Caribbean Jerk & Cuisine Ltd | Hospitality | 2018 |
| Lucy Mayo Beauty Hub Limited | Other services | 2025 |
| Lucy Mayo Hairdressing Academy Ltd | Education | 2025 |
| Lucy Mayo Limited | Other services | 2017 |
| Lucy Mayo Pamper Parties Ltd | Hospitality | 2025 |
| Luis Trans Ltd | Transport & logistics | 2025 |
| Luke John Richards Holdings Limited | Financial services | 2024 |
| Luke John Richards Limited | Professional & scientific | 2019 |
| Luke Reynolds Photography Ltd | Professional & scientific | 2020 |
| Lulu Luxury Candles Limited | Manufacturing | 2025 |
| Lumar Services Ltd | Information & communication | 2023 |
| Lumos View Limited | Hospitality | 2026 |
| Luton Buildings Solutions Ltd | Construction | 2023 |
| Luton Centre Limited | Health & social care | 2006 |
| Luton Osteopathic & Sports Injury Clinic Limited | Health & social care | 2003 |
| LUX Wheels Ltd | Wholesale & retail | 2023 |
| Luxe Shine Car Wash Ltd | Administrative & support | 2025 |
| Luxenberg Management Limited | Real estate | 2022 |
| Luxestone Properties Limited | Real estate | 2025 |
| Luxi Cars Ltd | Wholesale & retail | 2026 |
| Luxry Homes Ltd | Real estate | 2025 |
| Luxury Building Service Ltd | Construction | 2014 |
| Luxury Garden Rooms Ltd | Construction | 2020 |
| Luxury Travel Design Studio Limited | Administrative & support | 2025 |
| LWC Investments Limited | Construction | 2015 |
| LWP Traffic Management Limited | Construction | 2023 |
| LYD Fleure-Bleue Ltd | Health & social care | 2019 |
| Lydgate Fields Management Company Limited | Real estate | 2018 |
| Lynberg Ltd | Hospitality | 2026 |
| Lynx Services Ltd | Construction | 2015 |
| L’Esthetique Clinique Ltd | Health & social care | 2024 |
| M & C Land Ltd | Construction | 2015 |
| M & E Cable Jointing Limited | Construction | 2022 |
| M & I B Services Ltd | Construction | 2002 |
| M & S Scaffolding Services Limited | Construction | 2002 |
| M & WT C Limited | Wholesale & retail | 2000 |
| M Alex Transport Ltd | Transport & logistics | 2017 |
| M Boakye Ltd | Health & social care | 2014 |
| M Clarke Building Services Limited | Construction | 2016 |
| M G Driving Serv Ltd | Transport & logistics | 2013 |
| M L Accessories Limited | Other services | 1998 |
| M N Financial Services Ltd | Financial services | 2024 |
| M Pro Security Ltd | Administrative & support | 2022 |
| M R Carpet Solutions Limited | Wholesale & retail | 2019 |
| M Rusu. Electrical Ltd | Construction | 2024 |
| M S Installations Ltd | Construction | 2020 |
| M Sandhu Holdings Ltd | Construction | 2021 |
| M White Roofing & Guttering Solutions Limited | Construction | 2024 |
| M&D Building Ltd | Construction | 2021 |