| Jiff Ltd | Information & communication | 2023 |
| Jijigo Ltd | Hospitality | 2021 |
| JIM Gates Limited | Professional & scientific | 2018 |
| Jixu Limited | Professional & scientific | 2019 |
| JJ Cooperation Ltd | Hospitality | 2019 |
| JJB Roofing Ltd | Construction | 2026 |
| Jjcorp Ltd | Extraterritorial | 2008 |
| Jjec Limited | Hospitality | 2007 |
| JJL Europe Ltd | Wholesale & retail | 2019 |
| JJM Bespoke Construction Ltd | Construction | 2024 |
| JKS Group Ltd | Wholesale & retail | 2025 |
| Jlmp Ltd | Wholesale & retail | 2024 |
| JM Pestana Builders Ltd | Construction | 2026 |
| Jmko Ltd | Hospitality | 2025 |
| JMM Petrichor Ltd | Financial services | 2023 |
| Jmtech Ltd | Manufacturing | 2008 |
| JNJ Constructions Ltd | Construction | 2023 |
| JNJ Hentrics Accounting Services Ltd | Professional & scientific | 2011 |
| JNJ Nepos Limited | Real estate | 2018 |
| JOE & Juliet (UK) Ltd | Wholesale & retail | 2020 |
| Joe's Style Ltd | Other services | 2003 |
| Johanson United Ltd | Real estate | 2023 |
| JOI Construction Ltd | Construction | 2024 |
| Joinpur Central Mosque Ltd | Other services | 2024 |
| Jonathan Sayer Ltd | Information & communication | 2019 |
| Joyful Travel Ltd | Administrative & support | 2025 |
| Joystory Ltd | Transport & logistics | 2021 |
| JP & Solutions UK Ltd | Wholesale & retail | 2023 |
| JP Fire Installations Limited | Construction | 2002 |
| JP Lotus Ltd | Professional & scientific | 2023 |
| JPA Assisted and Supported Living Services Ltd | Health & social care | 2024 |
| JRF Project Management Limited | Information & communication | 2015 |
| JRL Choreography Limited | Arts & recreation | 2014 |
| JS Enterprise Group Ltd | Wholesale & retail | 2024 |
| JS F&B Ltd | Hospitality | 2019 |
| JS Holdings Group Ltd | Professional & scientific | 2019 |
| JS Partner F&B Ltd | Hospitality | 2020 |
| JSK Concepts Ltd | Professional & scientific | 2025 |
| JSY Cooperation 14 Ltd | Hospitality | 2023 |
| JSY Cooperation 15 Ltd | Hospitality | 2023 |
| JSY Cooperation Ltd | Hospitality | 2016 |
| JSY F&B Ltd | Hospitality | 2022 |
| JSY Food Ltd | Hospitality | 2022 |
| Jsysc Cooperation Ltd | Professional & scientific | 2021 |
| Jsysc F&B Ltd | Real estate | 2023 |
| Jsysc Ltd | Hospitality | 2021 |
| JT Food Trade Ltd | Hospitality | 2018 |
| Jt&C Limited | Administrative & support | 2021 |
| Jubilee Court (Golborne) Limited | Real estate | 2004 |
| Jump Biscuit Limited | Administrative & support | 2021 |
| JUN Property Services Ltd | Construction | 2020 |
| Juner Ltd | Professional & scientific | 2024 |
| Jung House Ltd | Hospitality | 2023 |
| Just Electricals & Plumbing Limited | Construction | 2019 |
| JVS Capital Limited | Administrative & support | 2024 |
| JYP Stay Ltd | Hospitality | 2024 |
| K & R Property Development Ltd | Real estate | 2019 |
| K & T Medical Ltd | Health & social care | 2020 |
| K - Karani Group Ltd | Other services | 2019 |
| K Delights Ltd | Hospitality | 2025 |
| K Motors London Ltd | Wholesale & retail | 2022 |
| K Sirah Sirah Limited | Professional & scientific | 2016 |
| K Smarthome Ltd | Construction | 2024 |
| K Spectrum Ltd | Health & social care | 2016 |
| K&A Construction Ltd | Construction | 2022 |
| K&G Kebab Ltd | Hospitality | 2019 |
| K&M Car&Van Limited | Wholesale & retail | 2025 |
| K&Se Co Limited | Wholesale & retail | 2022 |
| K&Y Management Ltd | Professional & scientific | 2024 |
| K-Bbq Ltd | Hospitality | 2024 |
| K-Foodstar Ltd | Wholesale & retail | 2023 |
| K-Okie Club Ltd | Other services | 2025 |
| K-One Food Ltd | Wholesale & retail | 2018 |
| K-Town Group Limited | Hospitality | 2018 |
| KA Brothers Ltd | Wholesale & retail | 2018 |
| Kaas Consultants Ltd | Professional & scientific | 2014 |
| Kaas Investment Ltd | Real estate | 2017 |
| Kahraman & Sevindik Ltd | Wholesale & retail | 2021 |
| Kaizen CPA (UK) Limited | Professional & scientific | 2022 |
| Kaizen IP Agent (UK) Limited | Extraterritorial | 2020 |
| Kami Barbers Ltd | Other services | 2024 |
| Kamis Barber Limited | Other services | 2010 |
| Kana Estates Ltd | Real estate | 2023 |
| Kandelle Designs Ltd | Professional & scientific | 2025 |
| Kane C Malcuit Construction Ltd | Construction | 2023 |
| Kane Malcuit Media Limited | Manufacturing | 2019 |
| Kangda Consulting Ltd | Professional & scientific | 2024 |
| Kansal Consultancy Limited | Professional & scientific | 2010 |
| Kanto Coffee Ltd | Hospitality | 2025 |
| Kaopu Shipping Ltd | Transport & logistics | 2025 |
| Kape&Pan Limited | Hospitality | 2017 |
| Kapihanproducts Ltd | Wholesale & retail | 2026 |
| Karen Packham Ltd | Administrative & support | 2018 |
| Kashsade LLP | | 2021 |
| Katecroft Limited | Professional & scientific | 1995 |
| Kaur Quality Clean Ltd | Administrative & support | 2025 |
| Kawaii Boba Limited | Hospitality | 2022 |
| KB Studio Limited | Professional & scientific | 2017 |
| KBB Consults Limited | Transport & logistics | 2017 |
| KBS Beauty Limited | Other services | 2025 |