| Letmefit Ltd | Construction | 2019 |
| Lets Move 4 U Limited | Real estate | 2022 |
| Letsbuild Kent Ltd | Construction | 2023 |
| Level UP Tuitions Ltd | Education | 2024 |
| Levie Limited | Wholesale & retail | 2017 |
| Levie Property Ltd | Real estate | 2024 |
| Lexnis Capital Limited | Real estate | 2026 |
| Lexnis Residential Security Ltd | Administrative & support | 2024 |
| Leybourne Chase Pre-School Ltd | Education | 2013 |
| LGF Services Ltd | Information & communication | 2023 |
| Lghandyman Ltd | Construction | 2021 |
| LH BIM Solutions Ltd | Professional & scientific | 2026 |
| LHC Electrical Limited | Construction | 2025 |
| Liberated by Love Services Ltd | Professional & scientific | 2022 |
| Licence to Success Limited | Administrative & support | 2012 |
| Life Safety Fire and Security Limited | Professional & scientific | 2010 |
| Life's Mojo Ltd | Wholesale & retail | 2020 |
| Lifecom Radio CIC | Information & communication | 2025 |
| Lifesafety Systems Limited | Administrative & support | 2011 |
| Lifeways Solutions Limited | Administrative & support | 2023 |
| Lift Assist Limited | Construction | 2016 |
| Lift CON Ltd | Construction | 2017 |
| Light House Electrical Contractors Ltd | Construction | 2024 |
| Light Takeaways Ltd | Hospitality | 2025 |
| Lighthouse Psychology Training Limited | Education | 2022 |
| Lime Court Management (Eltham) Limited | Households | 1986 |
| Lime Services Group Ltd | Information & communication | 2019 |
| Limelit Solutions Limited | Professional & scientific | 2010 |
| Liminal Climate Ltd | Professional & scientific | 2025 |
| Lincoln Site Management & Construction Services Ltd | Construction | 2013 |
| Linda Nails Gravesend Ltd | Other services | 2026 |
| Lindfield Electrical Services Limited | Other services | 2014 |
| Lindley Limited | Financial services | 2022 |
| Lindsay Mechanical Engineering Ltd | Construction | 2025 |
| Lindz Limited | Professional & scientific | 2006 |
| Lingo Ventures Ltd | Information & communication | 2024 |
| Linh's Nails & Beauty Ltd | Other services | 2026 |
| LINK19 College Ltd | Education | 2018 |
| Linkon Ltd | Real estate | 2008 |
| Links & I Ltd | Wholesale & retail | 2023 |
| Links 2 Logistics Limited | Transport & logistics | 2023 |
| Links Consultancy (UK) Limited | Professional & scientific | 2002 |
| Lins Flowers Limited | Wholesale & retail | 2022 |
| Lion Heart Landscapes Limited | Extraterritorial | 2023 |
| Lionbet UK Ltd | Information & communication | 2025 |
| LIP Fillers London Ltd | Other services | 2018 |
| LIT Customs Ltd | Transport & logistics | 2024 |
| Litha Design Consultancy Limited | Professional & scientific | 2018 |
| Little Beautifuls Boutique Ltd | Wholesale & retail | 2017 |
| Little Blossom Nursery and Day Care Limited | Health & social care | 2024 |
| Little Bower Limited | Real estate | 1991 |
| Little Explorers Kindergarten Ltd | Education | 2013 |
| Little Leafe Stars Football Camp Ltd | Education | 2025 |
| Little Lush Box Ltd | Wholesale & retail | 2023 |
| Little Paper Bird Ltd | Wholesale & retail | 2022 |
| Little Stars Child Minder Limited | Health & social care | 2022 |
| Little Stars House Ltd | Education | 2016 |
| Little White Dress Bridal Outlet Ltd | Wholesale & retail | 2021 |
| Little.Big Limited | Wholesale & retail | 2017 |
| Littlebearzprinting Ltd | Wholesale & retail | 2023 |
| Liv.U Limited | Transport & logistics | 2019 |
| Live B&G Limited | Wholesale & retail | 2018 |
| Live Constructions Ltd | Construction | 2022 |
| Live Love & Shine Ltd | Hospitality | 2018 |
| Livijay Properties Limited | Construction | 2020 |
| Liviu Construction Limited | Construction | 2020 |
| Liviu Pasca Holding Limited | Transport & logistics | 2024 |
| Livraz Ltd | Transport & logistics | 2022 |
| Lizbeez Limited | Administrative & support | 2004 |
| LJA Plumbing + Heating Ltd | Construction | 2015 |
| LKI Construction Ltd | Construction | 2026 |
| LKT Properties Ltd | Real estate | 2026 |
| LLL Management Ltd | Information & communication | 2013 |
| LM Profix Ltd | Construction | 2017 |
| LMC Property Solutions Ltd | Real estate | 2023 |
| LMM Trans Ltd | Wholesale & retail | 2023 |
| LN Property Services Ltd | Construction | 2021 |
| LO LO Associates Ltd | Wholesale & retail | 2018 |
| Local Chippy Ltd | Hospitality | 2019 |
| Lock Door and Shutters Ltd | Manufacturing | 1998 |
| Lockedtrading Ltd | Wholesale & retail | 2025 |
| Locks 4 Trucks Limited | Manufacturing | 2024 |
| Locks for Vans Limited | Administrative & support | 2004 |
| Loghmani Properties Limited | Real estate | 2020 |
| Logical Building Services Ltd | Construction | 2013 |
| Loginexa Global Ltd | Transport & logistics | 2026 |
| Logy Express Ltd | Transport & logistics | 2024 |
| Loka Ltd | Manufacturing | 2022 |
| LOL Sofas Ltd | Wholesale & retail | 2023 |
| Lola LUX Ltd | Professional & scientific | 2019 |
| Lolan Ltd | Transport & logistics | 2023 |
| Lolax Ltd | Transport & logistics | 2019 |
| London Airport Facilities Ltd | Construction | 2019 |
| London Circuits Ltd | Construction | 2016 |
| London Pirates Basketball Club Ltd | Arts & recreation | 2019 |
| London Plumbing & Electrical Ltd | Wholesale & retail | 2020 |
| London Plumbing Supplies Ltd | Wholesale & retail | 2023 |
| London Road (Romford) Management Company Limited | Households | 1994 |
| London SE Project Ltd | Construction | 2019 |
| London Site Solutions Ltd | Water & waste | 2019 |