| Loch HR Limited | Administrative & support | 2022 |
| Loch Law Limited | Professional & scientific | 2012 |
| Loch Learning Limited | Professional & scientific | 2021 |
| Loch Mediation Limited | Professional & scientific | 2012 |
| Loch Wellbeing Limited | Professional & scientific | 2020 |
| Lockley Consulting Limited | Administrative & support | 2022 |
| LOCKSM8 Limited | Other services | 2024 |
| Lockwall Ltd | Manufacturing | 2018 |
| LOCO49 Ltd | Wholesale & retail | 2019 |
| Lodestone Healthcare Limited | Health & social care | 2002 |
| Logium Limited | Professional & scientific | 2007 |
| Logix Property LLP | | 2022 |
| Lois Browning Financial Limited | Financial services | 2015 |
| Loksafe Limited | Extraterritorial | 2005 |
| Loksafe Services Limited | Extraterritorial | 2005 |
| Lolabelle Ltd | Administrative & support | 2017 |
| London Arrows Group Limited | Public administration | 2023 |
| London Cognitive Behavioural Therapy Limited | Health & social care | 2016 |
| London EYE Surgery Partnership Limited | Health & social care | 2013 |
| London G&C Jewellery Limited | Manufacturing | 2015 |
| London Plastic Surgery Centre UK Limited | Health & social care | 2012 |
| London Road Studios Ltd | Professional & scientific | 2022 |
| Lone Anomaly Productions Ltd | Professional & scientific | 2022 |
| Longbow Court Management Company Limited | Real estate | 2007 |
| Longtail Advisory Limited | Professional & scientific | 2025 |
| Longview Technology Limited | Information & communication | 2024 |
| Lonsdale (Tunbridge Wells) Limited | Real estate | 2021 |
| Lonsdale Management Limited | Households | 2017 |
| Looking Glass Marketing Limited | Information & communication | 2018 |
| Looking Good Feeling Great Ltd | Wholesale & retail | 2020 |
| Loops Health CIC | Health & social care | 2026 |
| Lordcharm Design Limited | | 1985 |
| Lorien Films Limited | Information & communication | 2025 |
| Lorna Wright Design Limited | Professional & scientific | 2022 |
| Losk Ltd | Information & communication | 2020 |
| Lost Property of London Ltd | Wholesale & retail | 2009 |
| Lotus Homeopathy Limited | Health & social care | 2023 |
| Lotus Massage Studio Ltd | Health & social care | 2024 |
| Loucuras Ltd | Health & social care | 2023 |
| Louis & Aimee Ltd | Professional & scientific | 2020 |
| Louis Henri Ltd | Professional & scientific | 2007 |
| Love and Grace Ltd | Wholesale & retail | 2018 |
| Love Cooking Studio Ltd | Education | 2020 |
| Love IS a RUG Limited | Wholesale & retail | 2015 |
| Love the Game UK Ltd | Education | 2022 |
| Love Your JOB Ltd | Administrative & support | 2024 |
| Lower Green Domestic Services Limited | Administrative & support | 2014 |
| Lower Green Road Limited | Households | 2022 |
| Lower Green Road Management Company Limited | Households | 2020 |
| Lower Pantiles (Car Park and Auction Hall) Limited | Real estate | 2016 |
| Lower Pantiles (Datw) Limited | Real estate | 2016 |
| Lower Pantiles LLP | | 2011 |
| Lower Pantiles Management Company Limited | Real estate | 2011 |
| Loyalty Capital Holdings Ltd | Information & communication | 2025 |
| Loyalty Capital Limited | Financial services | 2025 |
| Loyco International Limited | Hospitality | 2010 |
| LPM Automation Ltd | Information & communication | 2014 |
| LPP Developments Limited | Real estate | 2004 |
| LPS CIO Advisory Ltd | Information & communication | 2026 |
| Lrmn Ltd | Health & social care | 2015 |
| LS Elliott Property Ltd | Real estate | 2021 |
| LSG Systems Ltd | Information & communication | 2026 |
| LST Direct Limited | Manufacturing | 2023 |
| LT Florals Ltd | Wholesale & retail | 2024 |
| LTR UK Essentials Ltd | Wholesale & retail | 2025 |
| Lucas Lucas Ltd | Real estate | 2002 |
| Lucemi (Freehold) Ltd | Real estate | 2017 |
| Lucemi Developments Limited | Real estate | 2011 |
| Lucemi LLP | | 2011 |
| Lucent Energy Ltd | Construction | 2025 |
| Lucent Flow Ltd | Construction | 2025 |
| Lucent Solar Ltd | Construction | 2025 |
| Lucky Strike Film Productions Limited | Information & communication | 2025 |
| Ludlow Holdings Limited | Real estate | 1970 |
| Lugia Ltd | Real estate | 2007 |
| Luis and COS Limited | Administrative & support | 2015 |
| Luis Drumond Ltd | Transport & logistics | 2018 |
| Luke Martin Consulting Limited | Information & communication | 2023 |
| Luke Mortimer Productions Ltd | Information & communication | 2026 |
| Luke Williams Design Limited | Professional & scientific | 2016 |
| Lumiere Sites Ltd | Information & communication | 2021 |
| Luminous Wellbeing Ltd | Professional & scientific | 2020 |
| Luna Accounting Ltd | Professional & scientific | 2017 |
| Luna Media Group Ltd | Professional & scientific | 2020 |
| Lunaria Landscapes Ltd | Administrative & support | 2025 |
| Lush Locks Official Limited | Other services | 2024 |
| Lusori Group Limited | Financial services | 2022 |
| Lusso Luxury Brands Ltd | Wholesale & retail | 2026 |
| Luton BS Limited | Construction | 2020 |
| LUX ET Veritas Consultancy Limited | Professional & scientific | 2026 |
| Luxe Associates Ltd | Wholesale & retail | 2015 |
| Luxe Electrical Limited | Construction | 2017 |
| LUXE360 Limited | Wholesale & retail | 2024 |
| Luxury & Boutique Hotels Limited | Professional & scientific | 2019 |
| Lwhb Ltd | Information & communication | 2018 |
| Lyell Properties Limited | Real estate | 2020 |
| Lyons Leisure Ltd | Hospitality | 2025 |
| Lyons P&H Limited | Construction | 2024 |
| Lyons Wharf (Tonbridge) Management Limited | Households | 2001 |
| L’Hibou Consultancy Limited | Professional & scientific | 2019 |