| LE Toy Van International Limited | Financial services | 2019 |
| LE Toy Van Limited | Wholesale & retail | 1995 |
| Lectus Capital Limited | Financial services | 2015 |
| Left-Wing Network Ltd | Information & communication | 2012 |
| Legal Certainty Services Limited | Professional & scientific | 2013 |
| LEI Safety Solution Ltd | Construction | 2025 |
| Leigh & Glennie Limited | Administrative & support | 2002 |
| Lewis a Creative Ltd | Information & communication | 2025 |
| Lewis of Sunningdale Limited | Wholesale & retail | 2004 |
| Lifeline Dental Agency Limited | Health & social care | 2013 |
| Lifetime Digital Planning Limited | Professional & scientific | 2019 |
| Lifetime Financial Management Intermediaries Ltd | Financial services | 2002 |
| Lighting Control Hire Limited | Administrative & support | 2023 |
| Lime Tree Court Burtons Road Limited | Professional & scientific | 2011 |
| Limpopo Biltong Floggers LLP | | 2026 |
| Linden Tree Group Limited | Administrative & support | 2025 |
| Linden Tree Surgeons Limited | Agriculture & fishing | 2020 |
| Lindens Consulting Services Limited | Professional & scientific | 2024 |
| Linkedengland Ltd | Professional & scientific | 2014 |
| Linkupnow Limited | Administrative & support | 2016 |
| Lionpearls Ltd | Professional & scientific | 2025 |
| Liskeard London Limited | Real estate | 2005 |
| Little Wilding Co Limited | Manufacturing | 2025 |
| Live Beautiful Ltd | Health & social care | 2016 |
| Livecolour Limited | Professional & scientific | 2014 |
| LLD Staffing Agency Ltd | Health & social care | 2026 |
| Lldsa Limited | Health & social care | 2024 |
| LM Designs Contract Interiors Limited | Professional & scientific | 2010 |
| LM Property Services (Ascot) Ltd | Real estate | 2024 |
| Lnpg Limited | Other services | 2011 |
| LOC 22 Ltd | Wholesale & retail | 2016 |
| Lockton Developments Ltd | Construction | 2020 |
| Locuminmotion Ltd | Health & social care | 2007 |
| Logistics First Ltd | Wholesale & retail | 2025 |
| Lola George Accommodations Ltd | Administrative & support | 2025 |
| London & Countryside Developments Limited | Construction | 1997 |
| London House Media Ltd | Information & communication | 2016 |
| London Prestige Drives Ltd | Transport & logistics | 2025 |
| London Psychiatry Limited | Health & social care | 2007 |
| London Urban Academy Ltd | Education | 2026 |
| Lookout Limited | Information & communication | 2012 |
| Lorna Dane Consulting Limited | Administrative & support | 2022 |
| Lotus Interiors Ltd | Professional & scientific | 2019 |
| Lotus YU Limited | Hospitality | 2022 |
| Lovique Beauty Ltd | Other services | 2020 |
| Lower Green Capital Ltd | Professional & scientific | 2018 |
| Lrrs Consulting Ltd | Information & communication | 2013 |
| LSL Club Limited | Administrative & support | 2026 |
| LTV Group Limited | Financial services | 2015 |
| Lulo Property Limited | Financial services | 2025 |
| Luma Skin Therapies Ltd | Health & social care | 2023 |
| Lume Corp Ltd | Wholesale & retail | 2025 |
| Luos Ltd | Information & communication | 2026 |
| Luxe Diamonds Ltd | Manufacturing | 2025 |
| LV Motors Ltd | Manufacturing | 2014 |
| Lwrnc Hair Ltd | Other services | 2024 |
| Lynda Yong Limited | Manufacturing | 1997 |
| Lyndale Enterprises (BTL) Ltd | Real estate | 2003 |
| Lyndale Enterprises (UK) Ltd | Real estate | 2002 |
| Lynton Services Limited | Professional & scientific | 2018 |
| Lyora Healthcare Services Ltd | Public administration | 2023 |
| M & J Stores Limited | Real estate | 2003 |
| M C Peat & Co. LLP | | 2011 |
| M C Peat Finance Company Limited | Financial services | 2011 |
| M&N Property Management Limited | Real estate | 2017 |
| M.R.S Dhaliwal LLP | | 2018 |
| M1 Accountants Ltd | Professional & scientific | 2024 |
| MA Food & Wine Ltd | Wholesale & retail | 2024 |
| Macari's Maidenhead Limited | Real estate | 1986 |
| Mackarn Services Limited | Professional & scientific | 2022 |
| Mackey Demolition Services Limited | Water & waste | 1972 |
| Macpips UK Limited | Real estate | 2023 |
| Maddison & Ward LLP | | 2026 |
| Maddison Ward Ltd | Professional & scientific | 2022 |
| Madina Nails Ltd | Other services | 2026 |
| Maid of Perfection Ltd | Other services | 2020 |
| Maidenhead College Ltd | Education | 2002 |
| Maidenhead Golf Club Limited(The) | Arts & recreation | 1937 |
| Maison Ascot Ltd | Arts & recreation | 2025 |
| Makeover Medi Spa Ltd | Other services | 2019 |
| Malgama Ltd | Information & communication | 2015 |
| Mamber Ltd | Professional & scientific | 2024 |
| Managing the Service Business Limited | Professional & scientific | 1987 |
| Mandrology Health Ltd | Information & communication | 2024 |
| Manorbier Estates Ltd | Real estate | 2025 |
| Manpreet&Sooraj Ltd | Real estate | 2024 |
| Mantus Management Skills Limited | Administrative & support | 2009 |
| Maple & Gray Limited | Manufacturing | 2012 |
| Maplewood Homes Holdings Limited | Real estate | 2016 |
| Marco Zane Proietti Limited | Extraterritorial | 2023 |
| Mariah Athenoz 316 Ltd | Real estate | 2024 |
| Marie C Rowe Ltd | Health & social care | 2025 |
| Marlow Dental Centre Limited | Health & social care | 2023 |
| Marquees Direct Limited | Administrative & support | 2000 |
| Marshall-Bailes Limited | Manufacturing | 2019 |
| Martinez Services Limited | Professional & scientific | 2001 |
| Masa Madden Interiors Ltd | Professional & scientific | 2023 |
| Masaya Limited | Professional & scientific | 2023 |
| Match CUT Limited | Administrative & support | 2012 |
| Materialeyes Ltd | Extraterritorial | 2017 |