| Longhop Limited | Real estate | 1998 |
| Longmoor Farm Consulting Ltd | Professional & scientific | 2016 |
| Longs Property Investments Limited | Real estate | 2022 |
| Loomina Limited | Manufacturing | 2006 |
| Loopeco Ltd | Wholesale & retail | 2019 |
| Loose Goose Ltd | Wholesale & retail | 2024 |
| Lothbury James Limited | Construction | 2017 |
| Lotus UK Property Investment Limited | Real estate | 2019 |
| Louder Audio Productions Ltd | Arts & recreation | 2023 |
| Louis John Limited | Real estate | 2019 |
| Loupa Estates Ltd | Real estate | 2023 |
| Love and Lilly Limited | Wholesale & retail | 2020 |
| Love Chloe Ltd | Manufacturing | 2021 |
| Love Local Group Ltd | Professional & scientific | 2024 |
| Love OUR Planet Ltd | Wholesale & retail | 2019 |
| LOW Carbon Engineering Ltd | Professional & scientific | 2014 |
| LOW FEE Recruitment Ltd | Administrative & support | 2017 |
| Lowdown Media Ltd | Other services | 2018 |
| Lowe Lighting Ltd | Information & communication | 2022 |
| Lowestoft Accounts Limited | Professional & scientific | 2025 |
| Lowri GP Services Limited | Health & social care | 2023 |
| Loxmede Electronics Limited | | 1977 |
| Loyal Plumbers Ltd | Construction | 2021 |
| LP Civils Ltd | Construction | 2024 |
| LP Worktop Specialists Ltd | Construction | 2021 |
| LPA (Birmingham) Ltd | Professional & scientific | 2024 |
| LPC Older Adults Ltd | Health & social care | 2024 |
| LPM Electrical Ltd | Other services | 2017 |
| LPM Projects Limited | Construction | 2026 |
| LRC Contractors Ltd | Construction | 2021 |
| LS Medserve Ltd | Health & social care | 2013 |
| LSC Property Investment Company Ltd | Real estate | 2023 |
| LSJ Events Limited | Construction | 2024 |
| LSL Sports Ltd | Other services | 2024 |
| Luca Construction Ltd | Construction | 2017 |
| Lucas Gabriel Consulting Ltd | Other services | 2024 |
| Lucentis Consultants Limited | Health & social care | 2024 |
| Lucian Removals Ltd | Transport & logistics | 2025 |
| Lucian's Constructions Ltd | Construction | 2015 |
| Lucid Strategy Ltd | Professional & scientific | 2024 |
| Lucid Studio Design Ltd | Professional & scientific | 2023 |
| Lucie Raufast Ltd | Professional & scientific | 2026 |
| Lucius Capital Ltd | Financial services | 2021 |
| Lucy’S Beauty Delights Ltd | Wholesale & retail | 2026 |
| Luiz Roberto Lira Cortez Limited | Other services | 2018 |
| Luke & BEN Brickwork Ltd | Construction | 2020 |
| Luke Clarke Camera Ltd | Information & communication | 2024 |
| Luke James Holdings Limited | Financial services | 2022 |
| Luke James Limited | Wholesale & retail | 2011 |
| Luke Patrick Events Ltd | Hospitality | 2025 |
| Luke Trainer MMA Ltd | Arts & recreation | 2026 |
| Luma Cricket Ltd | Wholesale & retail | 2026 |
| Lumenross Ltd | Professional & scientific | 2026 |
| Lumi Limited | Information & communication | 2024 |
| Luminance Care Services Limited | Administrative & support | 2025 |
| Lumos Networks Limited | Professional & scientific | 2025 |
| Luroq Ltd | Wholesale & retail | 2025 |
| Luton Moves Ltd | Transport & logistics | 2012 |
| Luxate Limited | Health & social care | 2014 |
| Luxe Developments Limited | Construction | 2023 |
| Luxe Home Designs & Refurbishments Ltd | Construction | 2023 |
| Luxe SMP Clinic (Stevenage) Ltd | Other services | 2022 |
| Luxeon Ltd | Real estate | 2025 |
| Luxrite Ltd | Wholesale & retail | 2009 |
| Luxury AA Cleaning Limited | Administrative & support | 2025 |
| Luxury Affordable Furniture Ltd | Wholesale & retail | 2020 |
| Luxury Nails 09 Ltd | Other services | 2024 |
| Luxury Nails 99 Ltd | Other services | 2024 |
| Luxxiti Limited | Professional & scientific | 2019 |
| Lvov Services Limited | Construction | 2011 |
| LVP Motorsport Limited | Arts & recreation | 2026 |
| LX4 Entertainment Productions Ltd. | Administrative & support | 2023 |
| Lynn Reynolds PA Services Limited | Administrative & support | 2019 |
| Lynsey Morris Aesthetics Limited | Other services | 2022 |
| Lytton Lodge Management Company Limited | Households | 1985 |
| LZ Constructions Specialist Ltd | Real estate | 2024 |
| LZ Homes Ltd | Real estate | 2025 |
| M and F Property Investment Ltd | Real estate | 2026 |
| M and S Ahmed SRV Limited | Other services | 2016 |
| M B Hitchin Limited | Other services | 2024 |
| M C Medical Consulting Limited | Health & social care | 2007 |
| M C Nebo Ventures Ltd. | Health & social care | 2019 |
| M Group (Plant & Fleet Solutions) Limited | Administrative & support | 2019 |
| M Group (Services) Limited | Financial services | 2016 |
| M Group Energy (Agility Eco Services) Limited | Professional & scientific | 2012 |
| M Group Energy (Bierce Surveying) Limited | Professional & scientific | 2006 |
| M Group Energy (Data Insight) Limited | Information & communication | 2019 |
| M Group Energy (Infrastructure) Limited | Financial services | 2019 |
| M Group Energy (Metering) Limited | Professional & scientific | 1995 |
| M Group Energy (Network Infrastructure) Limited | Administrative & support | 1930 |
| M Group Energy Limited | Professional & scientific | 2021 |
| M Group Highways Limited | Construction | 2020 |
| M Group Telecom (Fixed Network Solutions) Limited | Construction | 2011 |
| M Group Telecom (Mobile Network Solutions) Limited | Professional & scientific | 1998 |
| M Group Telecom (Technology Services) Limited | Information & communication | 1996 |
| M Group Telecom Holdings Limited | Financial services | 2005 |
| M Group Telecom Limited | Information & communication | 2016 |
| M Group Transport (M&E) Limited | Construction | 2011 |
| M Group Transport (Rail & Aviation) Limited | Construction | 1979 |
| M Group Transport Limited | Construction | 2003 |