| Lalouche LLP | | 2013 |
| Lambwath Hall Management Company Limited | Households | 2006 |
| Lanesun Management Limited | Households | 2017 |
| Langside Property Limited | Other services | 2025 |
| Larchfield Management Limited | Households | 2014 |
| Larkfield Mews Management Company Limited | Households | 2004 |
| Leadership and Strategic Change LLP | | 2008 |
| Ledaca Associates Limited | Real estate | 2012 |
| Ledgercomm Ltd | Information & communication | 2019 |
| Leisure Vouchers Ltd | Extraterritorial | 2007 |
| Lesness Residents' Association Limited | Households | 1978 |
| Levey Enterprises Ltd | Hospitality | 2022 |
| Leydene (Fareham) Management Company Limited | Households | 2007 |
| Leyton House Design Limited | Administrative & support | 2017 |
| Liberty Apartments Management Company Limited | Households | 2004 |
| Light Bulb Editing Limited | Information & communication | 2019 |
| Lime Villa Residents Association Limited | Households | 1986 |
| Linden Mews Management Company Limited | Households | 2004 |
| Linden Place Residents Management Company Limited | Households | 2006 |
| Linerear Limited | Real estate | 1986 |
| Liquid Recruitment Solutions Limited | Administrative & support | 2007 |
| Lisa Akesson Limited | Education | 2017 |
| Little Gymnasiums Ltd | Education | 2026 |
| Little Red Bear Ltd | Information & communication | 2007 |
| Little Wine Shop Ltd | Professional & scientific | 2022 |
| LMR PC Solutions Limited | Information & communication | 2008 |
| Locksley Gardens Management Company Limited | Households | 2005 |
| Lodge West Management Limited | Households | 2010 |
| London Building Equipment (UK) Limited | Construction | 1999 |
| London Building Equipment Holdings Ltd | Administrative & support | 2018 |
| London Building Equipment Limited | Construction | 2002 |
| London Building Properties Limited | Real estate | 2016 |
| Longlands Management Company Limited | Households | 1982 |
| Longreach Consulting Ltd | Professional & scientific | 2023 |
| Loose Change Ltd | Other services | 2015 |
| Lowengorra Limited | Real estate | 2018 |
| Lower MID Market Capital & Advisory Ltd | Professional & scientific | 2025 |
| LP Media Consulting Ltd | Professional & scientific | 2016 |
| Lucas Oliver Recruitment Limited | Administrative & support | 2013 |
| Lucerna Partners Limited | Professional & scientific | 2013 |
| Luke MAN and Van Services Ltd | Transport & logistics | 2015 |
| Luke Removals Ltd | Transport & logistics | 2021 |
| Lynmouth Colossus Way Management Company Limited | Households | 2009 |
| Lynwood Place Management Company Limited | Households | 1992 |
| M.R.S. Services Ltd | Construction | 2006 |
| MAC94 Consultancy Ltd | Professional & scientific | 2026 |
| Magnolia Colossus Way Management Company Limited | Households | 2009 |
| Maharg Limited | Information & communication | 2003 |
| Maintain Limited | Information & communication | 2018 |
| Maltbys Holdings Ltd | Manufacturing | 2024 |
| Management and Information System Consultancy Limited | Extraterritorial | 1999 |
| Manapany Ltd | Real estate | 2018 |
| Manfido Limited | Information & communication | 2013 |
| Manor Farm Barns Management Company (Crowell) Ltd | Households | 2022 |
| Manor Mills Residential Management Company Limited | Households | 2006 |
| Manor Park Construction (HGF) Limited | Construction | 2021 |
| Manor Park Construction (LR) Ltd | Construction | 2017 |
| Manor Park Construction (STC) Limited | Construction | 2018 |
| Manor Park Construction Limited | Construction | 2011 |
| Maple (231) Limited | Real estate | 2004 |
| Mappe Ltd | Professional & scientific | 2023 |
| Marine Crescent Folkestone Limited | Extraterritorial | 2004 |
| Marine Parade (Tankerton) Management Company Limited | Extraterritorial | 2003 |
| Markat Developments (Bushey) Ltd | Construction | 2019 |
| Markat Developments Ltd | Construction | 2018 |
| Marlow Motoring World Ltd | Wholesale & retail | 2024 |
| Marlow Regatta Limited | Arts & recreation | 2013 |
| Marlow Software Limited | Information & communication | 2004 |
| Martin's Electric Services Limited | Public administration | 2009 |
| Mary Twill Grove Management Company (Langland) Limited | Households | 2012 |
| Matrix Integrated Systems Inc. | | 1989 |
| Matteo & Luca's Little Coffee Company Ltd | Wholesale & retail | 2019 |
| Maxium Doors Ltd | Wholesale & retail | 2018 |
| MAY Fair Place (Arlesey) Management Co. Ltd | Households | 2019 |
| Mayfair Court Management (Wakefield) Limited | Households | 2004 |
| Mayfair Freehold Limited | Households | 1998 |
| MB2 Creative Limited | Manufacturing | 2021 |
| Mccollier Group Ltd | Administrative & support | 2024 |
| Mccullagh Facades Limited | Construction | 2025 |
| MCF Commercial Limited | Financial services | 2007 |
| Mcgrigor (Aldershot) Management Company Limited | Households | 2019 |
| MDM Consult Ltd | Information & communication | 2023 |
| Mead Lane (Chertsey) Management Company Limited | Households | 2013 |
| Medgene Precision Health Ltd | Health & social care | 2022 |
| Mediaholix Ltd | Information & communication | 2009 |
| Medterra International (UK) Ltd | Professional & scientific | 2021 |
| Melanies Cakes Ltd | Manufacturing | 2021 |
| Melissa Webb Limited | Hospitality | 2000 |
| Melville Associates Limited | Professional & scientific | 2024 |
| Merrileas (Oxshott) Management Company Limited | Households | 2021 |
| Merritt-Rock Ltd | Professional & scientific | 2019 |
| Metropolitan Place Management Company Limited | Households | 2002 |
| Microdata Ltd | Professional & scientific | 2025 |
| Middlesex Access Flooring Limited | Construction | 2023 |
| Middlesex Carpentry Holdings Limited | Financial services | 2025 |
| Middlesex Carpentry Limited | Construction | 2015 |
| Middlesex Developments Limited | Real estate | 2013 |
| Middlesex Facades Ltd | Construction | 2026 |
| Middlesex Fire Stopping Holdings Limited | Financial services | 2025 |
| Middlesex Fire Stopping Limited | Construction | 2014 |