| Lightlands Accounting Solutions Ltd | Professional & scientific | 2022 |
| Lightwater Adventure Golf Ltd | Arts & recreation | 2021 |
| Like Training Ltd | Real estate | 1991 |
| Lillibrooke Manor Limited | Real estate | 2015 |
| Lilypad Racing Ltd | Arts & recreation | 2005 |
| Limbasan Spedition Ltd | Transport & logistics | 2023 |
| Lime and Soda Club Ltd | Hospitality | 2025 |
| Linbrooke Services Limited | Construction | 2002 |
| Lincoln Occupational Health LLP | | 2012 |
| Linda Forsen Sound Limited | Information & communication | 2018 |
| Linden Dental Surgery Limited | Health & social care | 2007 |
| Lindsay Central Developments Ltd | Construction | 2025 |
| Lindsay Solutions Limited | Information & communication | 2014 |
| Lingam Rani Property Investments Limited | Real estate | 2022 |
| Lingerie HUT Limited | Wholesale & retail | 2018 |
| Lingtren Images Limited | Information & communication | 2009 |
| Link Enrollment Services Limited | Administrative & support | 2023 |
| Linkco Limited | Arts & recreation | 1998 |
| Links Sports Retail Partnership Limited | Wholesale & retail | 2009 |
| Linkturn (UK) Limited | Construction | 1999 |
| Linkwave Associates Limited | Information & communication | 1995 |
| Linthatch Limited | Construction | 1982 |
| Lion Enterprises Limited | Information & communication | 2007 |
| Lions Sports Academy Limited | Education | 2016 |
| Lisa B Consultancy Ltd | Professional & scientific | 2023 |
| Lisburne Holdings Limited | Financial services | 1937 |
| Listening Incorporated Limited | Education | 2019 |
| Lister Hughes Ltd | Wholesale & retail | 2021 |
| Listhenact Limited | Professional & scientific | 2012 |
| Lithe Media Ltd | Information & communication | 2025 |
| Lithic BIO Ltd | Professional & scientific | 2026 |
| Little Barn Farm Limited | Professional & scientific | 2010 |
| Little Exploradores Ltd | Education | 2026 |
| Little Flowers Day Nursery Limited | Extraterritorial | 2012 |
| Little GEM Coffee Company Ltd | Wholesale & retail | 2020 |
| Little Karoo Farm Ltd | Agriculture & fishing | 2019 |
| Little Leo's Nursery Ltd | Education | 2006 |
| Little Loops by Lauren Ltd | Wholesale & retail | 2025 |
| Little Muddy ME Ltd | Education | 2023 |
| Little People Media Limited | Information & communication | 2016 |
| Little Red HEN Day Nursery Ltd | Health & social care | 2020 |
| Little Things Count Ltd | Wholesale & retail | 2023 |
| Little Threads Collection Limited | Wholesale & retail | 2022 |
| Little White Bear Ltd | Information & communication | 2014 |
| Little Works Limited | Health & social care | 2012 |
| Littlesteps NET Zero Ltd | Manufacturing | 2022 |
| Littoral Group Ltd | Professional & scientific | 2026 |
| Lived Experience Consulting Limited | Information & communication | 2025 |
| Living Projects Limited | Administrative & support | 2009 |
| Living Roots Ltd | Manufacturing | 2016 |
| Livingstones Travel World Ltd | Administrative & support | 2019 |
| Livrah Ltd | Wholesale & retail | 2019 |
| Livstyled Ltd | Other services | 2023 |
| LIW Europe Limited | Professional & scientific | 2017 |
| LJT Projects Limited | Manufacturing | 2010 |
| LJT Surgical Limited | Manufacturing | 2010 |
| LK Swim Academy Limited | Education | 2025 |
| LKW Consultancy Limited | Information & communication | 2010 |
| Llandefalle Limited | Professional & scientific | 2011 |
| Lleyn Estates Limited | Professional & scientific | 1962 |
| Lloyd Surveying Ltd | Construction | 2018 |
| LM Performance Ltd | Wholesale & retail | 2021 |
| LM PMO Services Ltd | Information & communication | 2010 |
| Lobium Ltd | Information & communication | 2021 |
| Lobs Consult Ltd | Professional & scientific | 2017 |
| Local MG Cleaning Services & Management Ltd | Administrative & support | 2025 |
| Localdouble Limited | Professional & scientific | 1997 |
| Lochinvar Solutions Ltd | Professional & scientific | 2024 |
| Lock N Track Ltd | Wholesale & retail | 2023 |
| Lock Serv Locksmiths Ltd | Administrative & support | 2013 |
| Lock Stars Security Ltd | Other services | 2026 |
| Lockside Media Services Ltd | Professional & scientific | 2013 |
| Lode Products and Services Limited | Wholesale & retail | 2008 |
| Logicalis Group Finance Limited | Financial services | 2019 |
| Logicalis Group Limited | Professional & scientific | 2000 |
| Logicalis International Group Holding Limited | Professional & scientific | 2023 |
| Logicalis International Limited | Information & communication | 2005 |
| Logicalis UK Limited | Information & communication | 1999 |
| Logicon Limited | Transport & logistics | 2010 |
| Logos Scientific Engineering Ltd | Construction | 2021 |
| Logrhythm Limited | Professional & scientific | 2008 |
| Logsfinder Ltd | Wholesale & retail | 2025 |
| Logsta UK Ltd | Transport & logistics | 2020 |
| Lohgarh Ltd | Real estate | 2020 |
| LOL Maidenhead Limited | Education | 2025 |
| London Aluminium Glazing (UK) Ltd | Other services | 2016 |
| London Belgravia Brokers Limited | Financial services | 2014 |
| London Belgravia Holdings Limited | Financial services | 2019 |
| London Belgravia Limited | Information & communication | 2011 |
| London Belgravia Surveyors Limited | Financial services | 2016 |
| London Bridge Ltd | Professional & scientific | 2017 |
| London City Clinic Ltd | Health & social care | 2022 |
| London Country BUS Services Limited | Extraterritorial | 2024 |
| London International Agency Ltd | Education | 2021 |
| London IS Trading Ltd | Hospitality | 2021 |
| London K&B Limited | Financial services | 2022 |
| London Lash Lounge Maidenhead Ltd | Other services | 2025 |
| London VIP Executive Ltd | Transport & logistics | 2024 |
| Londonburg Limited | Professional & scientific | 2012 |
| Lonemondial Limited | Professional & scientific | 2020 |