| LH Controls Ltd | Construction | 2016 |
| LHA Lettings Ltd | Real estate | 2013 |
| LHA Property Services Limited | Real estate | 2013 |
| LHE Estates Limited | Real estate | 2023 |
| Lhynes Consulting Ltd | Professional & scientific | 2025 |
| Liberty Quarter Management Company Limited | Real estate | 2022 |
| Life Change Care Ltd | Health & social care | 2014 |
| Life Love and Loss Ltd | Health & social care | 2012 |
| Lifeline United Healthcare Solutions Ltd | Administrative & support | 2016 |
| Lifescore Limited | Information & communication | 2016 |
| Liftro LLP | | 2025 |
| Liga Property Services Ltd | Real estate | 2018 |
| Light My Space Ltd | Professional & scientific | 2017 |
| Light Smiles Limited | Health & social care | 2014 |
| Light the Dark Productions Ltd | Administrative & support | 2023 |
| Lightfoot Travel Limited | Administrative & support | 2012 |
| Lightning Machining Ltd | Manufacturing | 2009 |
| Lightning Strike Productions Ltd | Other services | 2022 |
| Lilford Gardens Management Ltd | Real estate | 2022 |
| Lillygrange Limited | Construction | 2003 |
| Lily Nails & Beauty (Salisbury) Ltd | Other services | 2022 |
| Limb Solutions Limited | Administrative & support | 2005 |
| Lime Stuff Limited | Wholesale & retail | 2011 |
| Lime Tree House Consulting Limited | Information & communication | 2013 |
| Limitless Clinical Case Management Ltd | Health & social care | 2026 |
| Limitless Performance Workshop Ltd | Wholesale & retail | 2018 |
| Limivy Properties Limited | Real estate | 2025 |
| Limoni HCW Ltd | Other services | 2022 |
| Linc Dorsal Company Limited | Real estate | 2026 |
| Lincoln Manco Limited | Households | 2017 |
| Lind Consultancy Limited | Professional & scientific | 2025 |
| Linden Hire Ltd | Administrative & support | 2025 |
| Linden Plant Hire Limited | Administrative & support | 2000 |
| Line by Line Limited | Transport & logistics | 2002 |
| Ling Energy Limited | Construction | 2005 |
| Linkcore Services Ltd | Professional & scientific | 2026 |
| Linton Mcdowall Limited | Professional & scientific | 2023 |
| Linx Agency Limited | Professional & scientific | 2016 |
| Lion Engineering (Salisbury) Limited | Wholesale & retail | 2002 |
| Lions Bay Limited | Education | 2022 |
| Lions DEN Agency Ltd | Professional & scientific | 2025 |
| Lionsgate Residential Properties Ltd | Real estate | 2015 |
| Lisco Holdings Limited | Professional & scientific | 2025 |
| Litherland IP Services Limited | Professional & scientific | 2023 |
| Litod Limited | Professional & scientific | 2014 |
| Little Acres Residents Management Company Limited | Real estate | 2019 |
| Little Bowden Rise (Market Harborough) Management Company Limited | Households | 2016 |
| Little Chelsea Beauty Limited | Other services | 2023 |
| Little Chelsea Ltd | Other services | 2018 |
| Little Creative Limited | Other services | 2007 |
| Little Green Residents Management Company Limited | Households | 2021 |
| Little Monster Brewing Company Limited | Manufacturing | 2018 |
| Littlebourne Trustee Company Limited | Professional & scientific | 2019 |
| Littlemoor Lodge Management Company Limited | Households | 2003 |
| Littleton Evans Limited | Professional & scientific | 2008 |
| Liverdent Limited | Health & social care | 2021 |
| Livestock Improvement Corporation (UK) Ltd | Agriculture & fishing | 1983 |
| Livewire-Uk Talent Management Ltd | Arts & recreation | 2023 |
| Living Lots Limited | Real estate | 2025 |
| Livinghouse Holdings Limited | Financial services | 2025 |
| Livinghouse Limited | Wholesale & retail | 2000 |
| Livinspace Limited | Hospitality | 2007 |
| Liza's Little Explorers Ltd | Health & social care | 2024 |
| LJB (SW) Ltd | Hospitality | 2021 |
| Llanddwyn Properties Limited | Real estate | 2022 |
| Llangattock Court (Monmouth) Management Company Limited | Real estate | 2015 |
| Llys Meredith (Swansea) Management Company Limited | Households | 2015 |
| LM Properties Group Limited | Real estate | 2023 |
| Lmbc Limited | Construction | 2005 |
| Lmbud Limited | Financial services | 2012 |
| Lmhc Holdings Limited | Health & social care | 2024 |
| Lmhc Property Limited | Real estate | 2025 |
| LMK Properties Limited | Real estate | 2021 |
| LMR Bookkeeping Limited | Professional & scientific | 2020 |
| LMT Legal Limited | Professional & scientific | 2014 |
| Loam Project Limited | Professional & scientific | 2019 |
| Lobdale Limited | Professional & scientific | 2019 |
| Locally Sauced Ltd | Information & communication | 2025 |
| Lock Keepers Court Cardiff Management Company Limited | Households | 2003 |
| Lock's Lane Enterprises Ltd | Information & communication | 2020 |
| Lockerley Limited | Wholesale & retail | 2020 |
| Lockhart Armstrong Limited | Arts & recreation | 2002 |
| Lockhart Management Services Limited | Information & communication | 2016 |
| Lockwood Place (Bramford) Management Company Limited | Households | 2022 |
| Lockyer Homes Limited | Construction | 1995 |
| Lodestar Technology Holdings Ltd | Information & communication | 2025 |
| Lodestar Travel Technology Ltd | Information & communication | 2025 |
| Lodmoor Sands (Weymouth) Management Company Limited | Real estate | 2019 |
| Lofts and Ladders UK Ltd | Construction | 2021 |
| Logistics.Com (UK) Ltd | Education | 2014 |
| Logix Aero Limited | Wholesale & retail | 2016 |
| Lokomotiv Digital Limited | Information & communication | 2015 |
| Lomi Ltd | Professional & scientific | 2025 |
| London EYE Consultant Limited | Health & social care | 2021 |
| London F&B Group Ltd | Hospitality | 2018 |
| London Historians Limited | Other services | 2010 |
| London Irish Rugby Limited | Education | 2021 |
| London Quantum Group Limited | Information & communication | 2026 |
| London Road (Amesbury) Management Company Limited | Households | 1994 |
| London Wine Investors Limited | Financial services | 2010 |