| L a Estates (Property Services) Limited | Construction | 2008 |
| L a Estates Limited | Real estate | 2003 |
| L Briscoe Consultancy Ltd | Information & communication | 2022 |
| L Hathaway Carpentry Limited | Construction | 2015 |
| L Michalak Ltd | Transport & logistics | 2017 |
| L&A Scaffolding Services Limited | Construction | 2018 |
| L&M Walker Contract Flooring Ltd | Construction | 2023 |
| L. Johnson Ltd | Construction | 2010 |
| L.A.E.+ Ltd | Construction | 2016 |
| L.B Steel Installations Limited | Construction | 2019 |
| L.G Engineering Ltd | Manufacturing | 2019 |
| LA Duquesa View Ltd | Real estate | 2003 |
| LA Maison Noire Ltd | Real estate | 2021 |
| LA Milan Ltd | Administrative & support | 2017 |
| Laat Saab Group Ltd. | Manufacturing | 2017 |
| Lady Vanilla Ltd | Wholesale & retail | 2025 |
| Lady’S Touch Beauty Parlour Ltd | Other services | 2025 |
| Lafa Trans Ltd | Transport & logistics | 2020 |
| Laimis Ltd | Transport & logistics | 2025 |
| Lakeside Construction Services Limited | Construction | 2020 |
| Lakeview Property Maintenance Limited | Administrative & support | 2003 |
| Lalita Foods Limited | Hospitality | 2023 |
| Lambo Brothers Ltd | Administrative & support | 2016 |
| Lambrino Ltd | Administrative & support | 2024 |
| Lampford Limited | Professional & scientific | 2009 |
| Landcare Company Limited | Agriculture & fishing | 2026 |
| Landnet Logistics Limited | Transport & logistics | 2026 |
| Landscape Avenue Limited | Agriculture & fishing | 2010 |
| Landscape Concepts (Podington) Limited | Administrative & support | 2019 |
| Lane Refrigeration Ltd | Manufacturing | 2024 |
| Langage AD (UK) LLP | | 2011 |
| Langford J Limited | Health & social care | 2019 |
| Langford Performance Engineering Limited | Professional & scientific | 1989 |
| Langham Virtual Assistant Limited | Administrative & support | 2020 |
| Langley Logistics Ltd | Transport & logistics | 2021 |
| Langleybay Design & Build Limited | Construction | 2016 |
| Lanreanne Ltd | Real estate | 2024 |
| Lantea Electrical Services Ltd | Construction | 2025 |
| Laserco Limited | Construction | 1997 |
| Laszlo Luxe Ltd | Wholesale & retail | 2026 |
| Laumar Trans Limited | Transport & logistics | 2020 |
| Lauraphys Wellness Ltd | Health & social care | 2024 |
| Lawson Brooke Ltd | Professional & scientific | 2019 |
| Laxton Group Limited | Real estate | 2025 |
| LBN Logistics Limited | Transport & logistics | 2016 |
| LDC Lambrino Ltd | Hospitality | 2022 |
| LDK Group Ltd | Administrative & support | 2008 |
| LDM Leisure Ltd | Administrative & support | 2016 |
| Ldpa Limited | Arts & recreation | 2025 |
| LE Spice Merchant Ltd | Hospitality | 2026 |
| Learning Anorak Limited | Professional & scientific | 2008 |
| Learning for Life Education Trust | Education | 2015 |
| Lebeke Ltd | Construction | 2025 |
| Ledge and Kedge Limited | Real estate | 2022 |
| Ledger Break Limited | Professional & scientific | 2026 |
| LEE Composites Ltd | Professional & scientific | 2025 |
| LEE Green Consultants Ltd | Administrative & support | 2025 |
| Leek Road Holdings Limited | Construction | 2017 |
| Leeliam Limited | Health & social care | 2023 |
| Left & Right Holdings Ltd | Financial services | 2020 |
| Legacy Design & Build Ltd | Construction | 2026 |
| Legacy Workshop Ltd | Wholesale & retail | 2025 |
| Legumology Limited | Manufacturing | 1999 |
| Leibrandt & Co Ltd | Professional & scientific | 2023 |
| Leicestershire Investments Ltd | Real estate | 2019 |
| Leighton Bros. Entertainment Ltd | Hospitality | 2025 |
| Leimen Ltd | Construction | 2019 |
| Lemesh Properties Ltd | Real estate | 2022 |
| Lenny Integrity-Care Limited | Health & social care | 2016 |
| LEO & Laurentiu Ltd | Transport & logistics | 2019 |
| LER Films and Distribution Ltd | Information & communication | 2020 |
| Leslie Wood Limited | Construction | 2014 |
| Lesm Ltd | Hospitality | 2018 |
| Lespm Ltd | Hospitality | 2025 |
| LET2INVEST Ltd | Professional & scientific | 2003 |
| Letsflip Ltd | Real estate | 2025 |
| Let’S GET Plastered Limited | Construction | 2025 |
| Level Living Ltd | Other services | 2017 |
| Levi’N Ellie Ltd | Health & social care | 2026 |
| Lewis Harvey Events Ltd | Administrative & support | 2024 |
| Lexicus Developments Limited | Construction | 2016 |
| Lexicus Renewables Limited | Other services | 2023 |
| LFV Services Limited | Professional & scientific | 2026 |
| Liam Mandarin Garden Ltd | Hospitality | 2019 |
| Lian Construction Ltd | Construction | 2021 |
| Libra Building Limited | Information & communication | 2025 |
| Lifestyle Conversions Limited | Administrative & support | 2004 |
| Lightning Vehicle Movements Ltd | Transport & logistics | 2020 |
| Lilies Valley Limited | Real estate | 2021 |
| Lilium Naturals Ltd | Wholesale & retail | 2019 |
| Lilley Property Developments Limited | Administrative & support | 2009 |
| Lilliemac Ltd | Transport & logistics | 2015 |
| Lilliput Glass Holdings Limited | Financial services | 2018 |
| Lilliput Holdings Limited | Financial services | 2015 |
| Lilt Solutions Limited | Information & communication | 2015 |
| Lilycuddles Retail Group Limited | Wholesale & retail | 2018 |
| Lilystone Homes Limited | Construction | 2007 |
| Lina Trading Ltd | Hospitality | 2026 |
| Linden Asset Management Limited | Construction | 1998 |
| Linden Beck Limited | Real estate | 2022 |