| Leacroft (EG) Management Limited | Households | 2000 |
| Lead Generation Nation Ltd | Professional & scientific | 2019 |
| Lead the Way Care Services Ltd | Health & social care | 2023 |
| Leader Trucks Limited | Wholesale & retail | 1986 |
| Leaders Factory International Limited | Other services | 2007 |
| Leaders in Sports Coaching Limited | Education | 2025 |
| Leadership & Education Consultants Ltd | Other services | 2018 |
| Leading Technology Europe Limited | Information & communication | 2016 |
| Leafy Way Care & Support Services Ltd | Health & social care | 2024 |
| Lean Prop Limited | Real estate | 2024 |
| Leani Consulting Limited | Professional & scientific | 2007 |
| Leap Frog Nursery Limited | Health & social care | 2018 |
| Learners' Needs Tutoring Ltd | Information & communication | 2012 |
| Learning Academy (UK) Limited | Education | 2008 |
| Learning World Montessori Limited | Education | 2017 |
| Lease Management Limited | Administrative & support | 2015 |
| Leaseformal Property Management Limited | Real estate | 1994 |
| Leasehold Law LLP | | 2014 |
| Leasha World Empire Limited | Wholesale & retail | 2015 |
| Leather Wagon Company Limited(The) | Real estate | 1978 |
| Leatherhead Limited | Hospitality | 2025 |
| Leccy Co Ltd | Construction | 2022 |
| Leckhampton Place (Cheltenham) Management Company Limited | Households | 2015 |
| Leckhampton Place Management Limited | Households | 1990 |
| Lecton Place Management Limited | Households | 2009 |
| Ledgers Ltd | Professional & scientific | 2008 |
| LEE Elphick Engineering Services Ltd | Information & communication | 2013 |
| LEE Smith Ltd | Extraterritorial | 2022 |
| Leematsbag Limited | Manufacturing | 2023 |
| Leena Ltd | Construction | 2025 |
| Lees Garden Centre Limited | Wholesale & retail | 2017 |
| Leewood Court Management Company Limited | Households | 1978 |
| Legacy Accountings Services Ltd | Professional & scientific | 2024 |
| Legacy AI Limited | Education | 2026 |
| Legacy Auto & Plant Imports Ltd | Wholesale & retail | 2026 |
| Legacy by EMN Ltd. | Health & social care | 2021 |
| Legacy Cheer and Dance Limited | Arts & recreation | 2013 |
| Legacy Cheer Athletics Ltd | Arts & recreation | 2022 |
| Legacy Management & Holdings Limited | Real estate | 2024 |
| Legacy Residential Ltd | Real estate | 2025 |
| Legacy Towers Limited | Real estate | 2015 |
| Legal Property Group Ltd | Real estate | 2019 |
| Legal Temple Limited | Professional & scientific | 2025 |
| Legends L & L Limited | Hospitality | 2021 |
| Legends Racing Limited | Information & communication | 2019 |
| Legh House Management Company Limited | Households | 2002 |
| Legwood Court Management Limited | Households | 1984 |
| Leigh Green (Sandbach) Management Company Limited | Households | 2013 |
| Leigh Place Management Company Limited | Households | 2003 |
| Leigh Rachael Hall Ltd | Professional & scientific | 2018 |
| Leighton Consulting Ltd | Professional & scientific | 2026 |
| Leinster Trading Ltd | Hospitality | 2013 |
| Leith Towers Management Limited | Households | 1982 |
| Leixure Resorts Ltd | Information & communication | 2024 |
| Leiyah Ltd | Information & communication | 2025 |
| Lenbel Ltd | Manufacturing | 2025 |
| Lenelby Road (Tolworth) Management Company Limited | Households | 1993 |
| Lenio Consultants Ltd | Professional & scientific | 2021 |
| Lense Limited | Professional & scientific | 2025 |
| Lenses of Croydon CIC | Professional & scientific | 2024 |
| Lenzo Enterprises Ltd | Wholesale & retail | 2021 |
| Lenzo Holdings Ltd | Financial services | 2024 |
| Lenzo Properties Ltd | Real estate | 2024 |
| LEO P&M (UK) Co., Ltd | Wholesale & retail | 2020 |
| LEO Roofing & Building Ltd | Construction | 2011 |
| Leo's Home Improvements Ltd | Construction | 2019 |
| Leojay Ltd | Administrative & support | 2025 |
| Leon Digital Marketing Ltd | Information & communication | 2017 |
| Leon Property Solutions Ltd | Manufacturing | 2025 |
| Leon's Building Services Ltd | Construction | 2020 |
| Leona LEE Ltd | Information & communication | 2016 |
| Leone Real Estate Limited | Real estate | 2023 |
| Leonette Services Limited | Health & social care | 2013 |
| Leonik Limited | Financial services | 2011 |
| Leopard Transport Ltd | Transport & logistics | 2021 |
| Leopep Limited | Transport & logistics | 2017 |
| Leopold Butchers Limited | Wholesale & retail | 2023 |
| Leosak Ltd | Real estate | 2022 |
| LES Calices Properties Ltd | Real estate | 2025 |
| LES Calices Restaurant Ltd | Hospitality | 2015 |
| LES Margo Limited | Real estate | 2021 |
| Leslie Arms Croydon Limited | Real estate | 2022 |
| Lester Control Systems (Group) Ltd | Manufacturing | 2025 |
| Lester Control Systems (Holdings) Limited | Manufacturing | 2014 |
| Lester Control Systems Limited | Manufacturing | 1984 |
| LET ME Helpp Limited | Administrative & support | 2015 |
| Let's Go Gospel Ltd | Arts & recreation | 2023 |
| LET- Buy-Invest Properties Limited | Real estate | 2016 |
| Letgold Limited | Administrative & support | 1993 |
| Lets Explore Day Nurseries Limited | Health & social care | 2018 |
| Lets Explore Holdings Limited | Financial services | 2018 |
| Leve Kitchens Ltd | Wholesale & retail | 2021 |
| Level Developments Holdings Limited | Financial services | 2024 |
| Level Developments Limited | Manufacturing | 1987 |
| Levens Court Residents, Association Limited | Households | 1971 |
| Levens View (Ulverston) Management Company Limited | Households | 2020 |
| Lever Edge Convenience Store Ltd | Wholesale & retail | 2008 |
| Levvio Ltd | Professional & scientific | 2022 |
| Lewisham Project Football Club Limited | Arts & recreation | 2024 |
| Lexaa Technologies Ltd | Information & communication | 2025 |