| JAB Topco Limited | Financial services | 2014 |
| Jabdo Properties Ltd | Real estate | 2009 |
| Jabsys Limited | Information & communication | 2011 |
| JAC Group Ltd | Arts & recreation | 2026 |
| Jacapo Limited | Professional & scientific | 2018 |
| Jacaranda Capital Partners Limited | Financial services | 2013 |
| Jack Developments Ltd | Real estate | 2019 |
| Jack of Junction Ltd | Health & social care | 2019 |
| Jackie Heath Consulting Ltd | Professional & scientific | 2026 |
| Jacob's Motors Limited | Wholesale & retail | 2017 |
| Jacobea Limited | Health & social care | 2024 |
| Jacques Bouvier Ltd | Wholesale & retail | 2018 |
| Jadeh Limited | Professional & scientific | 2023 |
| Jads Properties Ltd | Real estate | 2019 |
| JAF Investments Limited | Real estate | 2024 |
| Jaffersons Energy Consultants Ltd | Professional & scientific | 2020 |
| Jafftek Limited | Information & communication | 2017 |
| JAG Finance Ltd | Professional & scientific | 2023 |
| Jaguar Instruments Ltd | Extraterritorial | 2015 |
| JAH Property Company Limited | Other services | 2013 |
| JAHAJ1 Limited | Real estate | 2020 |
| JAK Services Limited | Other services | 2015 |
| JAK Testing Services Ltd | Administrative & support | 2016 |
| Jakat Accounting Solutions Limited | Professional & scientific | 2020 |
| Jake Martin Inc Ltd | Wholesale & retail | 2015 |
| Jakovorl Ltd | Manufacturing | 2025 |
| Jaks Consultancy Ltd | Information & communication | 2017 |
| JAL Consultancy Solutions Ltd | Information & communication | 2014 |
| Jalice Accounts Ltd | Professional & scientific | 2016 |
| Jalil Consultancy Ltd | Information & communication | 2016 |
| Jamaica Heart Limited | Education | 2015 |
| James Calvert Limited | Professional & scientific | 2012 |
| James Grosvenor Ltd | Professional & scientific | 2015 |
| James Hart-Dyke Limited | Arts & recreation | 2011 |
| James Joinery UK Limited | Construction | 2011 |
| James Mcewan Property Services Ltd | Administrative & support | 2009 |
| James Services Herts Limited | Administrative & support | 2023 |
| James Shaun Holdings Limited | Real estate | 2024 |
| James Wren Ltd | Real estate | 2020 |
| James, Wilson & Boyd Consulting Ltd. | Professional & scientific | 2017 |
| Jameson Services Limited | Information & communication | 2016 |
| Jamesr Ltd | Information & communication | 2025 |
| Jamie Baker Quantity Surveying Limited | Professional & scientific | 2019 |
| Jamjar Cars Limited | Wholesale & retail | 2022 |
| Jammy Frog Limited | Professional & scientific | 2015 |
| Jams Group Limited | Wholesale & retail | 2025 |
| Jams Kitchen Limited | Hospitality | 2009 |
| Jamsign Limited | Administrative & support | 2003 |
| Jamspoel Ltd | Real estate | 2026 |
| Jamy Construction Limited | Construction | 2020 |
| Janard Holdings Ltd | Financial services | 2026 |
| Jane LE BON Limited | Administrative & support | 2004 |
| Jane Winn Consultancy Ltd | Administrative & support | 2024 |
| Janems Care Services Ltd | Health & social care | 2024 |
| Jani-Tec Services Ltd | Professional & scientific | 2013 |
| Jansel Square Limited | Real estate | 2021 |
| Janus Services Ltd | Information & communication | 2017 |
| JAP Infotech Ltd | Information & communication | 2011 |
| JAPANESE4X4PARTS Ltd | Wholesale & retail | 2010 |
| Jaqi Ltd | Information & communication | 2023 |
| Jara Technologies Limited | Information & communication | 2026 |
| Jardin Properties Limited | Real estate | 2018 |
| Jaremi Ltd | Other services | 2019 |
| Jars Property Limited | Real estate | 2015 |
| Jasco IT Limited | Information & communication | 2011 |
| Jash Integration Consultancy Services Ltd | Information & communication | 2012 |
| Jaso Civil Engineering Ltd | Construction | 2013 |
| Javi Global PVT Ltd | Manufacturing | 2025 |
| Javid Khan Limited | Health & social care | 2013 |
| Jawad Engineering Limited | Construction | 2012 |
| Jawhara Jewellery Limited | Wholesale & retail | 2016 |
| JAY Danev Limited | Wholesale & retail | 2024 |
| JAY Horwood Cleaners Ltd | Administrative & support | 2014 |
| JAY Property Services Ltd | Real estate | 2025 |
| Jayaa Limited | Professional & scientific | 2011 |
| Jayashree Consulting Ltd | Extraterritorial | 2012 |
| Jayasingha Associates Ltd | Professional & scientific | 2019 |
| Jayceehum Carers Ltd | Health & social care | 2025 |
| Jayceehum Constructions, Building & Maintenance Ltd | Construction | 2021 |
| Jayceehum Estate Agent Ltd | Real estate | 2010 |
| Jayceehum Motors Ltd | Wholesale & retail | 2013 |
| Jayceehum Movies Production Ltd | Information & communication | 2021 |
| Jayceehum Music Records Ltd | Wholesale & retail | 2021 |
| Jayceehum Recruitment Agency Ltd | Administrative & support | 2010 |
| Jayceehum Security Ltd | Administrative & support | 2021 |
| Jaykay Leisure UK Limited | Professional & scientific | 2009 |
| Jaytee Interiors Limited | Construction | 2005 |
| Jaytek Solutions Ltd | Information & communication | 2019 |
| Jayworth Limited | Real estate | 2025 |
| Jayworth Subco Limited | Real estate | 2025 |
| Jazel Ltd | Wholesale & retail | 2025 |
| Jazz Print Solutions Ltd | Manufacturing | 2020 |
| Jazz Property Ltd | Real estate | 2024 |
| Jazz ‘EM UP! Ltd | Wholesale & retail | 2023 |
| Jazz’S Cutz Limited | Other services | 2024 |
| JB Lifting Ltd | Administrative & support | 2009 |
| JB Medicare Limited | Health & social care | 2018 |
| JB Stone Cool Ltd | Construction | 2018 |
| JB Surveying Services Ltd | Professional & scientific | 2023 |
| JB Tanning Services Limited | Other services | 2020 |