| KKT Property Ltd | Real estate | 2023 |
| Klassique Dental LAB Limited | Manufacturing | 2012 |
| Klear KAY Driving School Limited | Education | 2025 |
| KM Chicken & Pizza Limited | Hospitality | 2022 |
| Kmarsh Plumbing & Heating Ltd | Construction | 2018 |
| Kmgvgc Ltd | Real estate | 2022 |
| KMN Real Estate Group Ltd | Real estate | 2020 |
| KNC Global Software Ltd | Information & communication | 2023 |
| Knightly & Ioannes Limited | Real estate | 2018 |
| KNP BS Ltd | Real estate | 2025 |
| Kntp Group Limited | Wholesale & retail | 2026 |
| Kobibenson Ltd. | Real estate | 2013 |
| KOC Nights Ltd | Hospitality | 2018 |
| Kody Catering Ltd | Hospitality | 2025 |
| Kohinoor Takeaway (Mitcham) Ltd | Hospitality | 2015 |
| Kojo Investments Limited | Professional & scientific | 2011 |
| Kola BR Ltd | Manufacturing | 2023 |
| KOM Enterprises Ltd | Hospitality | 2025 |
| Konpa London Ltd | Arts & recreation | 2024 |
| Kons Clothing Ltd | Wholesale & retail | 2025 |
| Konstruct Wixe Ltd | Construction | 2019 |
| Koya Fruits & VEG Ltd | Wholesale & retail | 2026 |
| KP Beauty Salon Limited | Other services | 2024 |
| Kpje Limited | Administrative & support | 2024 |
| Kpsa Investment Group Ltd | Financial services | 2025 |
| Kraker Solutions Limited | Administrative & support | 2020 |
| Kratos Attire Ltd | Wholesale & retail | 2018 |
| Krave Spot Ltd | Hospitality | 2022 |
| Krew Logistics Ltd | Transport & logistics | 2026 |
| Krishna Convenience Limited | Wholesale & retail | 2019 |
| Kronos Workforce Ltd | Administrative & support | 2026 |
| KRS and VM Services Limited | Professional & scientific | 2022 |
| KS Pipework Ltd | Construction | 2026 |
| KS Plumbing Ltd | Construction | 2019 |
| Ksiga Ltd | Financial services | 2025 |
| Ksl&T Ltd | Education | 2020 |
| Ksoap Ltd | Wholesale & retail | 2022 |
| KST UK Properties Ltd | Real estate | 2020 |
| KT Property Investments Limited | Extraterritorial | 2026 |
| KT20 Construction Ltd | Construction | 2024 |
| KTM Enterprise Limited | Other services | 2022 |
| Kumarji Letting Limited | Real estate | 2024 |
| Kupic UK Ltd | Wholesale & retail | 2026 |
| Kusonix Studios Limited | Information & communication | 2023 |
| Kwik Mart Ltd | Wholesale & retail | 2020 |
| Kwikresp Security FM Limited | Administrative & support | 2024 |
| KYY Clothing Limited | Wholesale & retail | 2024 |
| KZ Smart Investments Ltd | Real estate | 2021 |
| L & H Fried Chicken Ltd | Hospitality | 2019 |
| L & K Connections Limited | Real estate | 2021 |
| L & S Event and Party Decoration Ltd | Hospitality | 2025 |
| L Anwar Limited | Health & social care | 2018 |
| L B DRY Cleaners Ltd | Other services | 2005 |
| L K Taxis Ltd | Transport & logistics | 2013 |
| L M Building and Maintenance Limited | Construction | 2021 |
| L M Building and Maintenance London Ltd | Construction | 2026 |
| L R Couriers Ltd | Transport & logistics | 2022 |
| L S Investments Ltd | Real estate | 2022 |
| L&G Business Solutions Ltd | Administrative & support | 2016 |
| L&G Loft & Extensions Ltd | Construction | 2023 |
| L&R Transit Ltd | Transport & logistics | 2026 |
| L&S Transportation Ltd | Wholesale & retail | 2025 |
| L&U Builders Ltd | Construction | 2022 |
| LA Casita Property Services London Ltd | Construction | 2022 |
| LA Dore London Limited | Other services | 2018 |
| LA Famiglia Proprieta Ltd | Real estate | 2025 |
| LA Petite Fleur Pre-School Ltd | Education | 2008 |
| LA Touche Management Limited | Real estate | 2022 |
| Labbaik Homes Ltd | Construction | 2024 |
| Lady Butter Ltd | Wholesale & retail | 2026 |
| Laings Corner Lease Ltd | Real estate | 2025 |
| Laings Corner Ltd | Real estate | 2025 |
| Lakay Kaly CIC | Administrative & support | 2026 |
| Lakey Apparel Limited | Wholesale & retail | 2017 |
| Lakhsmi Properties Limited | Real estate | 2026 |
| Lalux Operations Ltd | Construction | 2020 |
| Lalux Plumbing & Heating Ltd | Construction | 2018 |
| Lalux Plumbing Services Ltd | Construction | 2024 |
| Lamjo Ltd | Health & social care | 2011 |
| Lanco Property Services Ltd | Real estate | 2026 |
| Landldivision Ltd | Transport & logistics | 2023 |
| Landymore Construction Ltd | Construction | 2026 |
| Lang Investments Limited | Real estate | 2026 |
| Langdr AI Ltd | Information & communication | 2023 |
| Lanka Mortgage Services Limited | Other services | 2008 |
| Lanoire Limited | Real estate | 1995 |
| Larae Living Ltd | Wholesale & retail | 2025 |
| Larchoak Ltd | Hospitality | 2025 |
| Larry Walshe Ltd | Wholesale & retail | 2014 |
| Larry Walshe Property Limited | Real estate | 2023 |
| Laterna Partners Ltd | Other services | 2017 |
| Latifi Builders Ltd | Construction | 2025 |
| Latifiservices Limited | Construction | 2025 |
| Laurels London Ltd | Construction | 2024 |
| Laval Insights Consultancy Ltd | Manufacturing | 2025 |
| Lavender Fields Youth UK Ltd | Wholesale & retail | 2026 |
| Lawele Industries Ltd | Wholesale & retail | 2023 |
| Laxmidhar Limited | Wholesale & retail | 2024 |
| Laymax Contractors Ltd | Construction | 2012 |
| LBK Frenchlaw Limited | Professional & scientific | 2015 |