| LKC Training & Support Services Ltd | Education | 2024 |
| LKN Trading Ltd | Wholesale & retail | 2025 |
| LL Media Consulting Limited | Professional & scientific | 2021 |
| LMA Sports Limited | Arts & recreation | 2021 |
| LMR Events Ltd | Administrative & support | 2024 |
| LNP (Berkshire) Ltd | Construction | 2026 |
| Lock & Load Ltd | Transport & logistics | 2025 |
| Lock Rescue 247 Limited | Administrative & support | 2020 |
| Lockd Ltd | Information & communication | 2025 |
| Lockfit (Bracknell) Ltd | Administrative & support | 2023 |
| Lockhart Roofing and Brickwork Services Limited | Construction | 2017 |
| Loewenstein Medical UK Ltd | Wholesale & retail | 2014 |
| Logical Recruitment Partners Ltd | Administrative & support | 2014 |
| Loinpc Limited | Real estate | 2024 |
| Londis Bracknell Ltd | Wholesale & retail | 2009 |
| London Escolla Futsal Club Limited | Education | 2015 |
| London Giants CC Ltd | Arts & recreation | 2025 |
| Lonewolf Flooring Ltd | Construction | 2023 |
| Long ARM Counselling Limited | Health & social care | 2026 |
| Longshot Lane MOT Ltd | Wholesale & retail | 2026 |
| Loodi Ltd. | Manufacturing | 2017 |
| Lord Gulliver Productions Limited | Information & communication | 1978 |
| Lordan Medical Ltd | Health & social care | 2025 |
| Lords Private Finance TA Twyman Bradnick Ltd | Financial services | 2005 |
| Lorefur Limited | Manufacturing | 2024 |
| Lorelai Ltd | Information & communication | 2023 |
| LOS Indios Ltd | Professional & scientific | 2012 |
| Lotus Careers Ltd | Administrative & support | 2026 |
| Lotus Global Co Ltd | Information & communication | 2007 |
| Louder Than Ltd | Professional & scientific | 2020 |
| Love Brother Group Ltd | Professional & scientific | 2019 |
| Love in the Sky Ltd. | Arts & recreation | 2015 |
| Love Maps on Ltd | Information & communication | 2012 |
| Lovejoy Homes Limited | Construction | 1978 |
| Lozenge Management Limited | Real estate | 2011 |
| Ltpc Services Ltd | Construction | 2025 |
| LTS Media Ltd | Real estate | 2025 |
| Lubatti Limited | Wholesale & retail | 2008 |
| Luke Clark Productions Limited | Information & communication | 2025 |
| Luke Randall Fitness Limited | Arts & recreation | 2021 |
| Lulla by Claire Limited | Other services | 2025 |
| Lumina Windows Limited | Construction | 2025 |
| Lumine Properties Ltd | Real estate | 2025 |
| Lunchbox Agency Ltd | Professional & scientific | 2024 |
| Lupan Ltd | Transport & logistics | 2024 |
| Luqverse Ltd | Information & communication | 2026 |
| Lusso Cavendish Road LLP | | 2014 |
| LUX AID Competitions Ltd | Arts & recreation | 2026 |
| Luxe Hair and Beauty Limited | Other services | 2019 |
| Luxe Realty Ltd | Real estate | 2025 |
| Luxemech & Welding Ltd | Manufacturing | 2025 |
| Luxemove Solutions Limited | Transport & logistics | 2024 |
| Luxeproperty Business Solutions Limited | Real estate | 2025 |
| Lvhh Ltd | Real estate | 2024 |
| Lwrnc Training Ltd | Education | 2025 |
| Lynax Care Services Ltd | Health & social care | 2023 |
| Lynch Mechanical Services Limited | Construction | 2016 |
| Lynda Carroll Architects Limited | Professional & scientific | 2017 |
| Lynne Hughes Consulting Ltd | Professional & scientific | 2020 |
| M & B Training Limited | Arts & recreation | 2019 |
| M & J Landscapes & Groundworks Ltd | Administrative & support | 2018 |
| M & M Construction Services (Berkshire) LLP | | 2016 |
| M E G Construction Limited | Administrative & support | 2007 |
| M E G Mechanical Limited | Water & waste | 2013 |
| M Hall Consultancy Ltd | Professional & scientific | 2013 |
| M K Digital and Trades Ltd | Wholesale & retail | 2025 |
| M P Construction (Berkshire) Ltd | Construction | 2009 |
| M S Business Engineering Limited | Information & communication | 2014 |
| M Truss Ltd | Transport & logistics | 2018 |
| M& a Knight Consultants Limited | Other services | 2014 |
| M&Jj Wealth Management Ltd | Real estate | 2021 |
| M&M Contracts Ltd | Construction | 2011 |
| M&M Logistic Ltd | Transport & logistics | 2024 |
| M&P Decorating Contractors Ltd | Construction | 2023 |
| M.A.M.A. Bear Limited | Wholesale & retail | 2026 |
| M.A.N Prosperitas Limited | Real estate | 2018 |
| M2N-B Ltd | Construction | 2024 |
| M360SERVICES Ltd | Construction | 2018 |
| M7G Consulting Limited | Professional & scientific | 2026 |
| Mabel Castro Travel Ltd | Administrative & support | 2019 |
| Mace Revamp EB Ltd | Manufacturing | 2025 |
| Machinda Investments Limited | Administrative & support | 2025 |
| Machine Learning Street Talk Limited | Information & communication | 2024 |
| Maciek E.S. Electrical Services Ltd | Construction | 2013 |
| Mackbe Tech Ltd | Information & communication | 2019 |
| MAD Dog 1 Ltd | Real estate | 2025 |
| MAD Dog Otterbourne Ltd | Real estate | 2025 |
| MAD Dog Rotherham Ltd | Real estate | 2025 |
| Madalina Ghita Ltd | Professional & scientific | 2023 |
| Made With Love & Profanity Ltd | Other services | 2019 |
| Madira Beverages Ltd | Manufacturing | 2025 |
| Maestroforte Ltd | Information & communication | 2017 |
| Mafjar Marine Trading Limited | Transport & logistics | 2025 |
| Magdalenka Polish Delicatessen Limited | Wholesale & retail | 2007 |
| Maggies Snacks Limited | Hospitality | 2025 |
| Magnetic Nova Ltd | Wholesale & retail | 2026 |
| Maidenco Limited | Administrative & support | 2021 |
| Maidenhead Fruits Ltd | Wholesale & retail | 2020 |
| Maidens Green Ltd | Information & communication | 2007 |
| Maiii Group Ltd | Wholesale & retail | 2024 |