| Lark Valley Court Residents Association Limited | Extraterritorial | 1988 |
| Lark Valley Projects Limited | Construction | 2007 |
| Lark Valley Woodcraft Ltd. | Manufacturing | 2021 |
| Larkridge Property Group Ltd | Real estate | 2025 |
| Larkspool Rentals Limited | Extraterritorial | 2015 |
| Larkwood Lakes Ltd | Hospitality | 2020 |
| Laser Civil Engineering & Plant Hire Limited | Construction | 2014 |
| Laser Rust Removals Ltd | Administrative & support | 2025 |
| Laset Limited | Wholesale & retail | 2021 |
| Lash Magnifique Ltd | Manufacturing | 2017 |
| Lashedtoo Limited | Wholesale & retail | 2024 |
| Lashings FC Limited | Arts & recreation | 2018 |
| Lashings World XI Ltd | Arts & recreation | 2018 |
| Last Seven Days Ltd | Wholesale & retail | 2025 |
| Lastly Ltd | Administrative & support | 2024 |
| Lastolite Limited | Professional & scientific | 1961 |
| Lastpackluck Collectables Ltd | Wholesale & retail | 2024 |
| Latchingdon South Limited | Construction | 2014 |
| Late Check-In Limited | Administrative & support | 2003 |
| Lathbury Management Company Limited | Households | 2016 |
| Latino Ltd | Hospitality | 2024 |
| Latitude With John Ltd | Professional & scientific | 2025 |
| Latte E Miele Ltd | Professional & scientific | 2021 |
| Laucos Group Co., Ltd. | Extraterritorial | 2015 |
| Launch a Project Ltd | Information & communication | 2024 |
| Launchlead Ltd | Wholesale & retail | 2022 |
| Laura H Burton Ltd | Administrative & support | 2022 |
| Lauren Elizabeth Jewellery Ltd | Manufacturing | 2023 |
| Laurencandice Limited | Administrative & support | 2019 |
| Lavatoring Ltd | Wholesale & retail | 2025 |
| Lavender Barn Associates Limited | Professional & scientific | 2005 |
| Lavender Health & Social Care Limited | Health & social care | 2011 |
| Lavender Letter Studios Ltd | Information & communication | 2026 |
| Lavenir Management LLP | | 2021 |
| Laventure Capital Limited | Financial services | 2023 |
| Laveta Greenwood Ltd | Extraterritorial | 2023 |
| Lavi Consulting Limited | Health & social care | 2013 |
| Law Accent Limited | Professional & scientific | 2023 |
| Lawash Ltd | Wholesale & retail | 2024 |
| Lawrence Brackstone Food Consultancy Limited | Manufacturing | 2024 |
| Lawrence Consulting Ltd | Health & social care | 2016 |
| Lawshall Motorworks Ltd | Wholesale & retail | 2026 |
| Lawson's (Bury ST. Edmunds) Limited | Real estate | 1937 |
| Laxfield House Limited | Health & social care | 2013 |
| Laxpedia Ltd | Information & communication | 2023 |
| Lazy Bones Dairy Ltd | Wholesale & retail | 2026 |
| LB 2026 Ltd | Professional & scientific | 2026 |
| LB Atelier Ltd | Wholesale & retail | 2024 |
| LB Ecigs Ltd | Administrative & support | 2013 |
| Lb&F Services Ltd | Health & social care | 2026 |
| Lbav Limited | Hospitality | 2019 |
| Lbep Limited | Real estate | 2020 |
| LBG Technology Group Ltd | Information & communication | 2026 |
| Lbkp Ltd | Information & communication | 2025 |
| LC Clark Estates Ltd | Real estate | 2025 |
| LC DH Properties Limited | Real estate | 2024 |
| LC Property Suffolk Ltd | Real estate | 2025 |
| LC Rentals Limited | Administrative & support | 2014 |
| LC Systems Ltd | Professional & scientific | 2026 |
| Lckeasy Ltd | Wholesale & retail | 2025 |
| LCL Transport Limited | Transport & logistics | 2026 |
| Lcle Group Ltd | Financial services | 2024 |
| LCM Property Group Ltd | Real estate | 2025 |
| Lcut Pictures Ltd | Information & communication | 2023 |
| LCW Property Management Ltd | Real estate | 2024 |
| LDA Creative Limited | Wholesale & retail | 2020 |
| LDA Developments Ltd | Construction | 2016 |
| LDR Electrical Services Ltd | Construction | 2021 |
| LDS Learning Development Support CIC | Education | 2025 |
| LE Fontáine Ltd | Manufacturing | 2024 |
| LEA Hospitality Ltd | Extraterritorial | 2021 |
| Lead Shark Group Ltd | Professional & scientific | 2025 |
| Lead Tech Academy Limited | Education | 2026 |
| Leadership Capacity NOW Limited | Education | 2022 |
| Leading Edge Marketing Ltd | Information & communication | 2025 |
| Leading With Lean Ltd | Professional & scientific | 2023 |
| Leadlight Ltd | Information & communication | 2024 |
| Leads to Success Global Limited | Professional & scientific | 2005 |
| Leadswift Limited | Professional & scientific | 2026 |
| Leaf UP Ltd | Wholesale & retail | 2025 |
| Leahmaria Limited | Health & social care | 2017 |
| Leap School of Motoring Limited | Education | 2019 |
| Learn With Medics Ltd | Education | 2025 |
| Learning in Law Limited | Other services | 2025 |
| Leather Station Limited | Wholesale & retail | 2024 |
| Lectec Ltd | Construction | 2018 |
| Ledger & INK Limited | Professional & scientific | 2020 |
| Ledtage Limited | Wholesale & retail | 2026 |
| LEE Advisory Limited | Professional & scientific | 2023 |
| LEE Attridge Landscapes Limited | Administrative & support | 2018 |
| LEE Consultant Limited | Financial services | 2023 |
| LEE Patterson PGA Golf Professional LLP | | 2012 |
| LEE Woodham Electrical Services Limited | Construction | 2006 |
| Lee-Fletcher Ltd | Real estate | 2025 |
| Leeds Engineering Ltd | Professional & scientific | 2024 |
| Leeds Service Limited | Transport & logistics | 2019 |
| Leesan Business Ltd | Information & communication | 2021 |
| Legacy 2025 LLP | | 2025 |
| Legacy Global Holdings Limited | Financial services | 2025 |
| Legacy Group JPH Limited | Financial services | 2018 |