| Kalos and Muse Nails Ltd | Other services | 2026 |
| Kamm Properties Limited | Real estate | 2024 |
| Kayci Ltd | Wholesale & retail | 2023 |
| Kaydan Carpenters and Shopfitters Ltd | Construction | 2015 |
| Kds-Print Ltd | Manufacturing | 2019 |
| Kebab and Burger HUT (Canvey) Limited | Hospitality | 2017 |
| Keep an EYE Ltd | Construction | 2023 |
| Kent Sealants UK Limited | Construction | 2003 |
| Key-We Limited | Transport & logistics | 2024 |
| Keycode Style Limited | Information & communication | 1992 |
| Keyser Investments Limited | Construction | 2013 |
| Khaer Limited | Wholesale & retail | 2026 |
| Kimmie Cosmetics Ltd | Manufacturing | 2020 |
| Kimpearls Ltd | Hospitality | 2026 |
| Kinahenterprise Ltd | Wholesale & retail | 2022 |
| Kinetic Security Ltd | Administrative & support | 2023 |
| Kingfisher Home Improvements Ltd | Construction | 2010 |
| Kingsbury Cannon Limited | Professional & scientific | 2019 |
| Kingsdowne Medical Limited | Health & social care | 2003 |
| Kingsland Contracts Limited | Construction | 2026 |
| KIP Property Holdings Limited | Real estate | 2025 |
| Kirk Duffield Rails Limited | Construction | 2016 |
| Kitsworld’S Design and Print Limited | Professional & scientific | 2024 |
| Kixx Colchester Ltd | Education | 2022 |
| KJF Electrical Limited | Manufacturing | 2014 |
| Kjr&Smc Limited | Hospitality | 2017 |
| KK VET Referrals Limited | Professional & scientific | 2023 |
| Klevercart Ltd | Information & communication | 2025 |
| KLH Railway Engineering Limited | Construction | 2007 |
| KMG Consultancy Services Limited | Financial services | 2026 |
| Kofiara Limited | Hospitality | 2025 |
| Konrad Wolfe Practice Limited | Health & social care | 2010 |
| Kosov Congregation Ltd | Other services | 2022 |
| Koylu Limited | Hospitality | 2025 |
| Krihansell Ltd | Construction | 2021 |
| KSN Restaurant Ltd | Hospitality | 2025 |
| Kuveny Express Ltd | Wholesale & retail | 2025 |
| KVA Stores UK Ltd | Wholesale & retail | 2026 |
| KWAME1 Estate Agents Ltd | Real estate | 2025 |
| L & B Utilities Ltd. | Construction | 2017 |
| L & M Pump Specialists Ltd | Professional & scientific | 2015 |
| L . Webb Roofing Ltd | Construction | 2016 |
| L H Cladding Ltd | Construction | 2017 |
| L J & Sons Property Ltd | Other services | 2019 |
| L J Manning Services Ltd | Construction | 2013 |
| L K Barnard Ltd | Construction | 2018 |
| L M T Jewellery Limited | Other services | 2008 |
| L&B Hire Ltd | Administrative & support | 2023 |
| LA Dance Studio Ltd | Arts & recreation | 2025 |
| LA Petite Petanque Ltd | Hospitality | 2018 |
| Labyrinth Tanning Ltd | Other services | 2014 |
| Lambarlows Limited | Extraterritorial | 2024 |
| Land & Sea Restaurants Limited | Hospitality | 2022 |
| Lane and Hart Limited | Real estate | 2013 |
| Lauren Walsh Permanent Makeup & Skincare Ltd | Other services | 2022 |
| Lavan Estates Limited | Real estate | 2016 |
| Layton & Layton Limited | Financial services | 2013 |
| LC Electrical Solutions Limited | Construction | 2009 |
| LC Landlords Limited | Real estate | 2013 |
| LE Salon Chic Limited | Other services | 2011 |
| Leaping Gravy Capital Limited | Construction | 2024 |
| LEE Environmental Ltd | Professional & scientific | 2018 |
| Leesafe Limited | Water & waste | 1997 |
| Legacyearrings Ltd | Wholesale & retail | 2025 |
| Legacynecklaces Ltd | Wholesale & retail | 2025 |
| Legit Trade Ltd | Wholesale & retail | 2020 |
| Leigh Beck Tyres Ltd | Wholesale & retail | 2024 |
| Lenflo Cabling Ltd | Construction | 2021 |
| Leodesign Ltd | Construction | 2025 |
| Leonte Trading Limited | Transport & logistics | 2017 |
| Let’S Keep Moving CIC | Education | 2022 |
| Level UP Fitness Ltd | Arts & recreation | 2024 |
| Lewis Intelligence Limited | Administrative & support | 2022 |
| Lexcellent Consultancy Limited | Professional & scientific | 2022 |
| Liberty Computer Systems Limited | Information & communication | 1995 |
| Liberty Housing Group Ltd | Real estate | 2018 |
| Licensing Connect Ltd | Administrative & support | 2012 |
| Life on Four Legs Limited | Professional & scientific | 2019 |
| Lifestyle Fitness Gym Ltd | Health & social care | 2016 |
| Lilly Jean Catering Ltd | Hospitality | 2025 |
| Lilly Jean Recruitment Ltd | Administrative & support | 2025 |
| Limebrook Classic Cars Ltd | Wholesale & retail | 2022 |
| Link Collectibles Ltd | Wholesale & retail | 2024 |
| Links Forwarding UK Limited | Transport & logistics | 2013 |
| Lion Gate Productions Limited | Other services | 2025 |
| Lion M&V Ltd | Real estate | 2026 |
| Listig Ltd | Real estate | 2024 |
| Little Tewkes Nursery Limited | Education | 2012 |
| LJ Construction (UK) Ltd | Construction | 2011 |
| LJC Holdings Ltd | Other services | 2021 |
| Lkfutures Ltd | Real estate | 2022 |
| LMT Rail Solutions Ltd | Construction | 2014 |
| Lochwall Limited | Information & communication | 2024 |
| LON Utilities Ltd | Construction | 2018 |
| London & South East Electricals Ltd | Construction | 2012 |
| London Calligraphy Ltd | Manufacturing | 2020 |
| London Plant Room Services Limited | Professional & scientific | 2013 |
| London Training and Development Centre Limited | Education | 2013 |
| London Veterinary Services Limited | Professional & scientific | 2013 |
| Long Island City Ltd | Wholesale & retail | 2017 |