| Leda-Serv Limited | Administrative & support | 2004 |
| LEE Booth Partners Limited | Agriculture & fishing | 2002 |
| Leeds Metal Spinning Co.Limited(The) | Manufacturing | 1919 |
| Leehann Limited | Transport & logistics | 1986 |
| Leek Electrical Contractors Limited | Construction | 2000 |
| Lees Games Limited | Wholesale & retail | 2003 |
| Legh of Lyme Ltd | Real estate | 2002 |
| Leigh Decor Ltd. | Construction | 2001 |
| Leigh Glass Co. Limited | Manufacturing | 1974 |
| Leigh Joinery Company Limited | Manufacturing | 2001 |
| Leigh Specsavers Limited | Wholesale & retail | 1992 |
| Leigh Spinners Limited | Manufacturing | 1954 |
| Leigh Visionplus Limited | Wholesale & retail | 1993 |
| Leighton House Retirement Home Limited | Health & social care | 2004 |
| LEM Makerfield Mining Ltd. | Professional & scientific | 1997 |
| LEM Mining & Restoration Ltd. | Mining & quarrying | 1997 |
| LEM Resources Ltd. | Professional & scientific | 1997 |
| Lemontree Productions Limited | Information & communication | 2005 |
| LET the Sunshine in Ltd | Other services | 2007 |
| Let`S Relocate Limited | Real estate | 2006 |
| Lewis & Delaney Electrical Limited | Construction | 1997 |
| Lexham Hotel Limited | Hospitality | 1998 |
| Lexson Waste and Removal Limited | Other services | 2024 |
| Leyland Filtration Limited | Manufacturing | 1982 |
| Leyland Mill Lane Motors Limited | Wholesale & retail | 2004 |
| Leyland Timber Supplies Limited | Manufacturing | 2002 |
| Lifestyle Joinery Limited | Construction | 1998 |
| Light-U Limited | Wholesale & retail | 2006 |
| Lima Engineering (Polyurethanes) Limited | Manufacturing | 2002 |
| Limefield Estates Ltd | Real estate | 2007 |
| Limelight Signs Limited | Construction | 1990 |
| Limeoak Properties Limited | Construction | 2005 |
| LIN 888 Ltd | Hospitality | 2022 |
| Lindonwood Limited | Financial services | 1989 |
| Lineage UK Transport Limited | Transport & logistics | 1997 |
| Lineage UK Warehousing Limited | Manufacturing | 1955 |
| Lineneed Limited | Administrative & support | 2000 |
| Lingley Windows Limited | Construction | 2005 |
| Lingville Ltd | Extraterritorial | 2007 |
| Lion Springs Limited | Manufacturing | 1984 |
| Liquidthinker Limited | Professional & scientific | 2006 |
| Lirbai MAA Costcutter Limited | Wholesale & retail | 2011 |
| Lister Hartman Limited | Construction | 2007 |
| Little Peter Street Management Company Limited | Households | 1996 |
| Little Wonders Nursery and Educational Services Ltd | Education | 2007 |
| Littler & Associates Limited | Real estate | 2001 |
| Littler Machinery Holdings Limited | Financial services | 2016 |
| Littler Machinery Limited | Wholesale & retail | 1975 |
| LJF Engineering Limited | Professional & scientific | 2001 |
| LMK Services Ltd | Manufacturing | 2018 |
| Loans 4 U Limited | Professional & scientific | 1998 |
| Local List Limited | Professional & scientific | 2002 |
| Lodgestyle Limited | Real estate | 2002 |
| Loft House (Durham Avenue) Lancaster Limited | Households | 1984 |
| Lofthouse of Fleetwood Limited | Manufacturing | 1963 |
| Logan Homes (North West) Limited | Real estate | 2002 |
| Logiport Limited | Professional & scientific | 2005 |
| Loizou Leisure Limited | Arts & recreation | 1981 |
| Longden & Cook Healthcare Accountancy Practice Limited | Professional & scientific | 2003 |
| Lonsdale Garage Limited | Wholesale & retail | 2001 |
| Lonsdale Sterrix Ltd | Wholesale & retail | 2025 |
| Look Sharp Limited | Other services | 2003 |
| Lordfern Limited | Real estate | 1983 |
| LOT Geotechnics Limited | Professional & scientific | 2007 |
| Lowden Ripley Ltd | Wholesale & retail | 2025 |
| Lower Shaw Contract Services Limited | Administrative & support | 2004 |
| LOYALTY244 Limited | Wholesale & retail | 2025 |
| LTC Parent Ltd | Manufacturing | 2020 |
| Ltomo Ltd | Information & communication | 2018 |
| Luca Vanucci Limited | Wholesale & retail | 1980 |
| Ludlow Joinery Limited | Construction | 2007 |
| Lunan James Limited | Information & communication | 2005 |
| Lunesdale Home and Garden Limited | Wholesale & retail | 2003 |
| Luneside Studios Limited | Arts & recreation | 2007 |
| Lunorix Ltd | Wholesale & retail | 2025 |
| Lyalroc Enterprises (UK) Limited | Wholesale & retail | 1994 |
| Lyddesdale Courtyard Management Co. Ltd. | Real estate | 2006 |
| Lyeceum Academy Ltd | Education | 2023 |
| M & J Builders (Burnley) Limited | Construction | 1997 |
| M & K Consultants Ltd | Professional & scientific | 2000 |
| M B Autos NW MOT Limited | Wholesale & retail | 2024 |
| M Barrett & SON Limited | Other services | 2005 |
| M I T Recruitment Ltd. | Administrative & support | 1997 |
| M J Tattersall Limited | Transport & logistics | 1997 |
| M P a Hire Limited | Administrative & support | 2007 |
| M P Carroll Ltd | Construction | 2004 |
| M P Holdings UK Limited | Real estate | 2005 |
| M R Secretaries Limited | Professional & scientific | 2005 |
| M Schreiber and Sons Limited | Construction | 2003 |
| M T Hendrickse Limited | Real estate | 2003 |
| M. D. Coolair Limited | Construction | 2004 |
| M. Seddon Limited | Construction | 2001 |
| M.J.N. Worldwide Properties Limited | Real estate | 2002 |
| M.N. Flooring Limited | Construction | 2003 |
| M.P. Deaville Limited | Other services | 2003 |
| M.W. & G. Hough Limited | Construction | 2003 |
| Mabengwane Limited | Health & social care | 2015 |
| Machined Fabrications Ltd | Extraterritorial | 2002 |
| Machinery Applications Limited | Professional & scientific | 2007 |
| Mackenzie Trading Limited | Wholesale & retail | 2006 |