| LEE Fung 888 Ltd | Hospitality | 2020 |
| LEE Taman Limited | Extraterritorial | 2007 |
| LEE Williams Plumbing Services Limited | Construction | 2002 |
| Legacy Kids Ltd | Real estate | 2023 |
| Legacy Productions Limited | Information & communication | 2002 |
| Legal Services (London) Limited | Other services | 2003 |
| Legalpoint Limited | Professional & scientific | 2005 |
| Legend Gentleman Barbers Ltd | Other services | 2024 |
| Legends Bathrooms & Heating Limited | Professional & scientific | 2008 |
| Leigh Corner Management Company Limited | Households | 1986 |
| Leigham Autos Limited | Wholesale & retail | 1996 |
| Leightons Franchises Limited | Wholesale & retail | 1995 |
| Leisure Covers & Associated Trades Ltd | Administrative & support | 2016 |
| Leisure Marketing Services Limited | | 1983 |
| Leisurebase Limited | Administrative & support | 1989 |
| Leith Funerals Limited | | 1985 |
| Lejara Holdings Limited | Other services | 1983 |
| Leonard Oakley Contracts Limited | Construction | 1963 |
| Leonard Oakley Limited | Construction | 2004 |
| Leptos Limited | Professional & scientific | 2006 |
| Lerch Consulting Ltd | Professional & scientific | 2025 |
| Lesbourne Court Management Company Limited | Real estate | 2002 |
| Lester Lift Services Limited | Construction | 1973 |
| Let's Imagine Limited | Professional & scientific | 2006 |
| Leverside Property Management Company Limited | Households | 1991 |
| Lewis Services (Europe) Limited | Construction | 2000 |
| LEX Ventures Limited | Financial services | 2004 |
| Lexa Property and Investment Limited | Administrative & support | 2016 |
| LG & M Developments Ltd | Construction | 2018 |
| LGZ Services Ltd | Administrative & support | 2025 |
| Lichfield Gardens Residents Association Limited | Households | 1988 |
| Licone Consulting Ltd | Professional & scientific | 2018 |
| Lifesaver Direct Limited | Financial services | 2004 |
| Lifesource. Ltd | Real estate | 2020 |
| Light Tecnica Ltd | Professional & scientific | 2002 |
| Lightbulb Consults Limited | Professional & scientific | 2017 |
| Lighthouse Consulting Europe Limited | Professional & scientific | 2004 |
| Lighting Control Services Limited | Professional & scientific | 2005 |
| Lighting Controls Limited | Professional & scientific | 2004 |
| Lightlas Limited | Professional & scientific | 2018 |
| Lightstorm Trading Limited | Administrative & support | 1996 |
| Lightwater Grange Management Company (NO.2) Limited | Households | 1985 |
| Lightwater Newsagents Limited | Extraterritorial | 2003 |
| Liken Limited | Information & communication | 2003 |
| Lilliepink Limited | Wholesale & retail | 2019 |
| LIM Independent Living & Community Care Services Ltd | Health & social care | 2011 |
| Lime Street Insurance Company Limited | Financial services | 1979 |
| Limelight Accountancy Limited | Professional & scientific | 1993 |
| Limelight Engineering Limited | Professional & scientific | 2006 |
| Limes Fenton Ltd | Health & social care | 2005 |
| Limpsfield Chart Golf Club Trustee Company Limited | Other services | 1998 |
| Limpsfield Properties Limited | Real estate | 1986 |
| Lincoln Green and Company | | 1992 |
| Lincoln Hawk Consultants Limited | Manufacturing | 2003 |
| Linda Fams Collections Ltd | Wholesale & retail | 2022 |
| Linda Koscia Limited | Professional & scientific | 2002 |
| Linden Place Management Company Limited | Households | 1987 |
| Lindminster Limited | | 1984 |
| Lindner Commercial Limited | Construction | 1983 |
| Line 23 Limited | Information & communication | 2005 |
| Linfams Consultancy Ltd | Other services | 2018 |
| Linkfield Accident Management Limited | Wholesale & retail | 1996 |
| Links Support Limited | Information & communication | 2006 |
| Lion Gate Gardens Management Company Limited | Households | 1981 |
| Liphook Garage Limited | Wholesale & retail | 1985 |
| Lisa Property Limited | Other services | 1996 |
| Lisa Real Estate Limited | Other services | 1993 |
| Lithu Property Ltd | Real estate | 2026 |
| Little & Large Landscapes Limited | Administrative & support | 2004 |
| Little Antics Limited | Education | 2004 |
| Little Bookham Manor House School | Education | 1962 |
| Little Fosters Properties Limited | Real estate | 1984 |
| Little Star Drinks Ltd | Wholesale & retail | 2024 |
| Littlestrong Ltd | Wholesale & retail | 2001 |
| Liucheng UK Limited | Education | 2019 |
| Livigno Snow Limited | Administrative & support | 2005 |
| Lizzo UK Limited | Other services | 1990 |
| LJN Ltd. | Agriculture & fishing | 2012 |
| LK Away Ltd | Arts & recreation | 2024 |
| LKK Global Ltd | Wholesale & retail | 2016 |
| LL Events Limited | Construction | 2007 |
| Llama Promo Limited | Hospitality | 2003 |
| Lloyd & Wood Groundworks Limited | Construction | 2006 |
| Lloyds Distributors Ltd | Wholesale & retail | 2011 |
| LMT Payments Limited | Financial services | 2025 |
| Lo&Co Limited | Administrative & support | 2017 |
| Loane Construction & Carpentry Limited | Construction | 2013 |
| Local Link London Ltd | Information & communication | 2018 |
| Lodeview Limited | | 1982 |
| Lodge Close ( Property) Ltd | Households | 2014 |
| Lodge Close (Edgware) Limited | Real estate | 1996 |
| Logrun 94 Limited | Transport & logistics | 1979 |
| Londent Oral Care Ltd | Health & social care | 2023 |
| London (UK) Limited | Professional & scientific | 1999 |
| London Bach Society | Arts & recreation | 1999 |
| London Civil Engineering Limited | Professional & scientific | 1999 |
| London Gadget Repairs Limited | Other services | 2018 |
| London Gdns Ltd | Professional & scientific | 2020 |
| London in Bloom | Education | 1999 |
| London Industry Limited | Professional & scientific | 1999 |