| Lead Connex Limited | Professional & scientific | 2025 |
| Leading Solutions (UK) Ltd | Administrative & support | 2013 |
| Lectec Services Limited | Extraterritorial | 2012 |
| LEE Morgan Sport Limited | Arts & recreation | 2013 |
| Lekimech Ltd | Manufacturing | 2025 |
| Leon Riley Contracting Limited | Construction | 2024 |
| Less Than Retail Ltd | Wholesale & retail | 2024 |
| Lessmeas Ltd | Wholesale & retail | 2024 |
| Letford Joinery Limited | Construction | 2021 |
| Lexington Engineering Limited | Professional & scientific | 2019 |
| Life Mastery Universal Ltd | Education | 2018 |
| Lifestylem Commercial Cleaning Limited | Administrative & support | 2025 |
| Light Medical Ltd | Wholesale & retail | 2018 |
| Linkway Trade Limited | Wholesale & retail | 2024 |
| Lion Air Conditioning Ltd | Energy | 2019 |
| Lion Projects Limited | Construction | 2015 |
| Lithuanian Artisan Cheese Company Limited | Manufacturing | 2022 |
| Little Angels (Moreton) Limited | Education | 2017 |
| Little Red Wolf Ltd | Wholesale & retail | 2023 |
| Little Scholars Furniture Ltd | Manufacturing | 2023 |
| Liverpool Plastic Bonding Limited | Manufacturing | 1997 |
| Liverpool Precision Engineering Limited | Manufacturing | 2014 |
| Living Easy Ltd | Real estate | 2019 |
| Lizmontagens Installation Services Ltd | Other services | 2020 |
| LJA Research & Consultancy Limited | Arts & recreation | 2021 |
| LK Unique Properties Ltd | Hospitality | 2019 |
| LLG Enterprises Limited | Education | 2004 |
| LM Smart Detailing Ltd | Administrative & support | 2023 |
| Lockgate Security Ltd | Administrative & support | 2019 |
| Logan Mechanical & Automation Services Ltd | Professional & scientific | 2025 |
| Logistics.Shaws Ltd | Transport & logistics | 2015 |
| Lohon Ltd | Information & communication | 2025 |
| Loko Investments Ltd | Financial services | 2021 |
| Lola Design Studio Ltd | Professional & scientific | 2018 |
| Loma Surfaces Ltd | Wholesale & retail | 2025 |
| London Linen Management Limited | Administrative & support | 1957 |
| London Marine and Technology Company Limited | Manufacturing | 2002 |
| Look and Pick Ltd | Professional & scientific | 2025 |
| Loose | Health & social care | 2008 |
| Lord Nelson Tattoos Limited | Other services | 2008 |
| LOS Muertos Body Art Ltd | Health & social care | 2019 |
| Lottery Advisory Limited | Administrative & support | 2015 |
| Love Frocks Ltd | Wholesale & retail | 2026 |
| Love Nails 59 Ltd | Other services | 2026 |
| LP North One Limited | Wholesale & retail | 2022 |
| LP North Seven Limited | Wholesale & retail | 2022 |
| LR Creative Limited | Professional & scientific | 2016 |
| LR Events Ltd | Hospitality | 2025 |
| Lu-Ka Services Ltd | Construction | 2024 |
| Lucion Delta-Simons Ltd | Professional & scientific | 2003 |
| Lucion Group Limited | Professional & scientific | 2015 |
| Lucion Services Limited | Professional & scientific | 2008 |
| Lucion Survey Ltd | Professional & scientific | 1991 |
| Lumovolt Solutions Limited | Construction | 2025 |
| Luxury Health Ltd | Health & social care | 2021 |
| Lymm Property Management Ltd | Real estate | 2025 |
| Lynlea Services Limited | Administrative & support | 2011 |
| M & M Facades Limited | Construction | 2012 |
| M Alaudin Services Limited | Professional & scientific | 2017 |
| M Fallows Building Ltd | Construction | 2026 |
| M P Process Design Limited | Professional & scientific | 1995 |
| M P Storage & Blending Limited | Transport & logistics | 1988 |
| M Roberts Property Ltd | Real estate | 2019 |
| M S Huang Ltd | Hospitality | 2023 |
| M W Taxi Services Limited | Transport & logistics | 2014 |
| M&A Engineering Solutions Ltd | Professional & scientific | 2023 |
| M-Power Activity Services Limited | Other services | 2002 |
| M-Seft Ltd | Financial services | 2018 |
| M.D.A. Rail Limited | Administrative & support | 1998 |
| M.H. Electrical Distributors Limited | Wholesale & retail | 1990 |
| Maar Chicken Ltd | Hospitality | 2025 |
| MAC Electrical Cheshire Ltd | Construction | 2026 |
| MAC Landscapes Limited | Administrative & support | 2024 |
| MAC the Property Co Limited | Real estate | 2013 |
| Maciejczyk Transport Ltd | Transport & logistics | 2013 |
| Macs Automotive Ltd | Wholesale & retail | 2026 |
| Macy's Cafe Ltd | Hospitality | 2017 |
| Magna Investment Holdings Ltd | Financial services | 2026 |
| Magna Renewables Limited | Construction | 2018 |
| Magnum Tattoo Supplies Limited | Wholesale & retail | 2010 |
| Majek Driving Ltd | Transport & logistics | 2018 |
| Make Drive Ltd | Transport & logistics | 2018 |
| Malmesbury Park Properties Limited | Real estate | 2025 |
| Malshaw Investments Ltd | Real estate | 2022 |
| Malvya Group Limited | Construction | 2021 |
| MAM Brands Ltd | Wholesale & retail | 2025 |
| Manchester Organics Limited | Professional & scientific | 1996 |
| Mander Ryan Ltd | Professional & scientific | 2016 |
| Mango Hair and Makeup Ltd | Other services | 2018 |
| Manna Proteins Limited | Extraterritorial | 2008 |
| Mannasol Products Limited | Manufacturing | 2002 |
| Marantec Drives Limited | Extraterritorial | 2014 |
| Marantec UK Limited | Wholesale & retail | 1990 |
| Marauders Theatre Ltd | Arts & recreation | 2020 |
| Marine Services NW Limited | Professional & scientific | 2012 |
| Mark Green Gardening & Landscaping Ltd | Administrative & support | 2017 |
| Mark Greeve Accounting Ltd | Professional & scientific | 2007 |
| Mark Shannon Transport Ltd | Transport & logistics | 2021 |
| Marleys Mucky PUP Spa Ltd | Other services | 2021 |
| Marryan Supplies Limited | Wholesale & retail | 2026 |