| Kanyali Group Ltd | Wholesale & retail | 2025 |
| Kash Guards Security Limited | Administrative & support | 2023 |
| Kash Retail Essex Ltd | Wholesale & retail | 2025 |
| Kathryn Storrar Properties Limited | Real estate | 2018 |
| Kays Autospecialists Limited | Manufacturing | 2012 |
| KB Repairs Ltd | Wholesale & retail | 2026 |
| Kbshans Ltd | Wholesale & retail | 2023 |
| KEJ Consultancy Limited | Wholesale & retail | 2018 |
| Kestas Electrical Ltd | Construction | 2026 |
| Ketodel Services Ltd | Health & social care | 2019 |
| KG Vehicle Services Ltd | Wholesale & retail | 2014 |
| Kinesilab Ltd | Other services | 2022 |
| King Lifts Limited | Transport & logistics | 2019 |
| Kirby Electrics Limited | Construction | 2022 |
| Klic Electrical Ltd | Construction | 2013 |
| Klokwerk Ltd | Information & communication | 2017 |
| KLS Gatecraft Ltd | Manufacturing | 2026 |
| Knice Care Limited | Health & social care | 2022 |
| Knowledge Tool Box Ltd | Education | 2022 |
| Kobi-At Limited | Households | 2018 |
| Kong's Restaurant Limited | Hospitality | 2025 |
| Krate Records Limited | Information & communication | 2023 |
| KRN Specialist Ltd | Health & social care | 2023 |
| Kshan Property Ltd | Real estate | 2024 |
| Kuama Ltd | Manufacturing | 2021 |
| Kunes Bros Limited | Real estate | 2024 |
| L M Properties 1 Ltd | Real estate | 2024 |
| L-Tec Solutions Limited | Information & communication | 2016 |
| L.H. Electrical & Building Services Limited | Construction | 2012 |
| L.T.K. Investment Projects Limited | Wholesale & retail | 1980 |
| LA Maison Nannies Limited | Administrative & support | 2025 |
| Labami Consultancy Ltd | Professional & scientific | 2017 |
| Lakewater Estates Limited | Construction | 2002 |
| Lala Bazaar Ltd | Hospitality | 2019 |
| Lamberts Tool & Welding Supplies Limited | Wholesale & retail | 2000 |
| Lampits Convenience Ltd | Wholesale & retail | 2025 |
| Landscape Lottery Ltd | Construction | 2026 |
| Lanham's Leisure Ltd | Arts & recreation | 2025 |
| Lary & Dady Ltd | Transport & logistics | 2017 |
| Lavallos Solutions Ltd | Water & waste | 2026 |
| Lazy Sheep Company Ltd | Wholesale & retail | 2020 |
| LBF Services Limited | Information & communication | 2014 |
| LBN by Phelpsey Ltd. | Professional & scientific | 2015 |
| Lbolu IT Services Ltd | Professional & scientific | 2017 |
| LCD Solutions Ltd | Administrative & support | 2020 |
| LCI Trans Limited | Transport & logistics | 2020 |
| LD Williamson Services Ltd | Construction | 2024 |
| Ldsm Ltd. | Wholesale & retail | 2010 |
| LE Grave GAS and Heating Ltd | Construction | 2026 |
| LE Hope Refurbishments Ltd | Construction | 2015 |
| LE Purple Ltd | Hospitality | 2024 |
| Lead Legacy Ltd | Administrative & support | 2016 |
| LEE & Co Tax Accountants Limited | Professional & scientific | 2002 |
| LEE O'Sullivan Reward Solutions Ltd | Professional & scientific | 2020 |
| Legacy Engineering Services Ltd | Professional & scientific | 2026 |
| Legend Corringham Ltd | Other services | 2022 |
| Leman Limited | Transport & logistics | 1971 |
| Lendit Local Ltd | Administrative & support | 2025 |
| Lenval Limited | Construction | 2002 |
| Lesniewski Logistic Limited | Transport & logistics | 2019 |
| Level UP Soccer UK Ltd | Arts & recreation | 2023 |
| Lignum Wood Floor Company Ltd | Construction | 2022 |
| Lilac Building Maintenance Limited | Construction | 2024 |
| Lilac Property Group Limited | Real estate | 2024 |
| Limitless Learning Group CIC | Education | 2025 |
| Limo Construction Ltd | Manufacturing | 2019 |
| Lines Properties Limited | Real estate | 2020 |
| Lineside Limited | Construction | 2001 |
| Linford Food & Wine Ltd | Extraterritorial | 2014 |
| Lino&Lana Ltd | Wholesale & retail | 2025 |
| Little Bunnies Childcare Services Ltd | Health & social care | 2019 |
| Little Butterflies Pre-School Ltd | Health & social care | 2025 |
| Little Chestnuts Preschool Limited | Education | 2018 |
| Little Legs Buses Ltd | Transport & logistics | 2019 |
| Littlepond Ltd | Extraterritorial | 2005 |
| Liu's Lotus House Ltd | Hospitality | 2025 |
| Lius Enterprice Limited | Hospitality | 2022 |
| Living Water Housing Ltd | Real estate | 2023 |
| LJA Group Limited | Hospitality | 2026 |
| LJM Electrical Installations Limited | Construction | 2021 |
| Logic Resi 1 Ltd | Real estate | 2023 |
| Logic Resi 2 Ltd | Real estate | 2023 |
| Logic Resi Ltd | Real estate | 2023 |
| London VD Ltd | Other services | 2025 |
| London Yuet WAN Cantonese Opera Association Ltd | Arts & recreation | 2026 |
| Lotus Aesthetics and Skin Care Clinic Limited | Other services | 2024 |
| Louis Electrical Engineering Services Ltd | Energy | 2014 |
| LPM Engineering Services Ltd | Construction | 2026 |
| LS Flooring Limited | Construction | 2003 |
| LSL Realty Limited | Construction | 2022 |
| Lsso UK Ltd. | Information & communication | 2014 |
| LTR Holdings Ltd | Financial services | 2021 |
| LTR Trading Co Limited | Administrative & support | 2009 |
| Lucky Sweet Shop Ltd | Wholesale & retail | 2024 |
| Ludvigsen Mcmahon Limited | Professional & scientific | 2015 |
| Lumie Consultants Ltd | Administrative & support | 2023 |
| Lummi Ltd | Administrative & support | 2022 |
| Luxebargains Limited | Wholesale & retail | 2018 |
| M & D Autos Limited | Wholesale & retail | 2011 |
| M & L Reinforcements Limited | Construction | 1993 |