| Lixvora Ltd | Other services | 2026 |
| LJ Paralegal Services Limited | Professional & scientific | 2026 |
| LJD Packaging Ltd | Administrative & support | 2015 |
| LJT Construction Services Limited | Construction | 2015 |
| LJW Maintenance & Installation Limited | Construction | 2018 |
| LLA Marketing Services Limited | Professional & scientific | 2018 |
| Llamedos Trading Limited | Professional & scientific | 2002 |
| Llbrown Consulting Ltd | Information & communication | 2019 |
| LM Plumbing & Drainage Ltd | Construction | 2025 |
| LM Recruitment Ltd | Administrative & support | 2022 |
| LMG Financial Consulting Limited | Professional & scientific | 2021 |
| Local Gastros Ltd | Hospitality | 2022 |
| Local Helpie Ltd | Wholesale & retail | 2025 |
| Local Land Charges Institute | Other services | 2000 |
| Local Mobile Tyres Ltd | Wholesale & retail | 2026 |
| Loch MOY Properties Ltd. | Real estate | 2017 |
| Loci Construction Ltd | Construction | 2026 |
| Lockyerdecorating & Homeimprovements Ltd | Construction | 2025 |
| Lodge Court Management Company Limited | Households | 1988 |
| Lodge Farm Events Limited | Real estate | 2022 |
| Lodge Farm House Limited | Hospitality | 2019 |
| Lofs Publishing Ltd | Information & communication | 2025 |
| Logic Print Limited | Manufacturing | 2012 |
| Logic Properties Limited | Real estate | 2004 |
| Logik 7 Consulting Limited | Professional & scientific | 2020 |
| Lohmeyer Consulting Group Limited | Professional & scientific | 2024 |
| Loki Management Services Ltd | Professional & scientific | 2022 |
| London Clinic of Nutrition Limited | Health & social care | 2016 |
| London Cozy Escape Limited | Hospitality | 2025 |
| London Cozy Haven Limited | Hospitality | 2025 |
| London Cozy Retreat Limited | Hospitality | 2025 |
| London Cozy Stay Limited | Real estate | 2023 |
| London Science Tutors Limited | Education | 2012 |
| London Travel Clinic Limited | Administrative & support | 2010 |
| London UK Retail Ltd | Wholesale & retail | 2022 |
| Lonely Moon Ltd | Wholesale & retail | 2019 |
| Long Island Limited | Financial services | 1997 |
| Longmei Ltd | Wholesale & retail | 2024 |
| Looktech Recruitment Ltd | Administrative & support | 2026 |
| Loom and Form Ltd | Professional & scientific | 2017 |
| Loop AI Ltd | Manufacturing | 2024 |
| Loop Air Conditioning Ltd | Administrative & support | 2012 |
| Lordsman (Royston) Limited | Other services | 2018 |
| LOS Olvidados Limited | Information & communication | 2012 |
| LOS Reyes Limited | Hospitality | 2026 |
| Lost ARK Games Limited | Wholesale & retail | 2012 |
| Lotus Education Ltd | Education | 2012 |
| Lotus Management Investments Limited | Real estate | 2025 |
| LOU W Ltd | Information & communication | 2013 |
| Loughborough Taverns Ltd | Hospitality | 2017 |
| Love Dream Grow. Ltd | Other services | 2023 |
| Love Your Junk Limited | Transport & logistics | 2018 |
| Lower Green Farm Ickleford Limited | Agriculture & fishing | 2025 |
| Lowkey Clothing Ltd | Manufacturing | 2023 |
| Loxo Creative Ltd | Information & communication | 2019 |
| LPT (Holdings) Ltd | Financial services | 2023 |
| LS Land Limited | Construction | 2025 |
| LS Property & Renovations Ltd | Real estate | 2024 |
| LSG Ltd | Professional & scientific | 2025 |
| Lucas Lane Sports Club Limited | Real estate | 2019 |
| Lucca Consultancy Limited | Information & communication | 2009 |
| Luceat Investments Limited | Financial services | 2024 |
| Lucid Finance Services Ltd | Professional & scientific | 2026 |
| Lucinda Riley Investments Limited | Financial services | 2023 |
| Lucinda Riley Limited | Information & communication | 2011 |
| Lucy Lambert Co Limited | Education | 2025 |
| Luke James Developments Limited | Construction | 2021 |
| Luke O'Connor Services Limited | Professional & scientific | 2024 |
| Luma Consultancy Limited | Administrative & support | 2007 |
| Lumaura Connected Home Limited | Information & communication | 2025 |
| Lumina Corporate Finance Limited | Financial services | 2012 |
| Lumière Laser Ltd | Other services | 2023 |
| Luna's Aquarium Framework CIC | Information & communication | 2026 |
| Luton & District Roofing Contractors Ltd | Construction | 2019 |
| Luxury Nails 96 Ltd | Other services | 2023 |
| Lydgate Consultancy Ltd | Professional & scientific | 2020 |
| Lyles ROW Management Limited | Households | 2021 |
| Lyme-Bite Limited | Professional & scientific | 2024 |
| Lyon Holdings Ltd | Real estate | 2018 |
| Lyon Investments Ltd | Real estate | 2018 |
| Lyteviva Resources Limited | Health & social care | 2015 |
| Lytton Place Management Company Limited | Households | 2007 |
| Léorse Ltd | Wholesale & retail | 2024 |
| M & C Hearts Builders Ltd | Construction | 2019 |
| M & J Oakley Limited | Agriculture & fishing | 2011 |
| M & L Autocare Limited | Wholesale & retail | 2012 |
| M B Harris Plumbing & Heating Limited | Construction | 2017 |
| M C Products Limited | Manufacturing | 1994 |
| M C Thermal Insulations Limited | Construction | 2006 |
| M Development Services Limited | Construction | 2022 |
| M Goddard Plastering Ltd | Construction | 2024 |
| M Guest Limited | Health & social care | 2011 |
| M H Productions Ltd | Information & communication | 2012 |
| M J Accounting Services Ltd | Professional & scientific | 2018 |
| M J B Inter Link Ltd | Transport & logistics | 2020 |
| M J Granger Grounds Maintenance Limited | Administrative & support | 2002 |
| M Lang Brickwork Limited | Construction | 2014 |
| M O Dollimore Limited | Financial services | 2014 |
| M O'Leary & Sons Construction Limited | Construction | 2005 |
| M R Gooda's Heating & Plumbing Limited | Construction | 2025 |