| JO Truck Ltd | Transport & logistics | 2024 |
| Joalice Limited | Hospitality | 2019 |
| Joanna Halliday Limited | Financial services | 2014 |
| Joanne Dobie Limited | Administrative & support | 2013 |
| Joanne Mcgrath Planning Ltd | Professional & scientific | 2018 |
| Joanne Shaw Horse Sales Ltd | Other services | 2025 |
| Joashes Limited | Professional & scientific | 2020 |
| Jobbs Electricals Ltd | Professional & scientific | 2023 |
| Jobfinity Group Ltd | Financial services | 2020 |
| Jobfinity Ltd | Professional & scientific | 2021 |
| Jobfinity Systems Ltd | Information & communication | 2025 |
| Jobfinity Trading Ltd | Information & communication | 2025 |
| Jobologi Limited | Administrative & support | 2023 |
| Jobsons Lane Limited | Administrative & support | 2014 |
| Jodana Limited | Information & communication | 2014 |
| JOE Talbot 19 Racing Limited | Other services | 2024 |
| Joelett Limited | Manufacturing | 2013 |
| Joelett Properties Ltd | Real estate | 2021 |
| Jofitzp Limited | Information & communication | 2021 |
| Johansson Property Group Limited | Real estate | 2024 |
| John a Green Offshore Ltd | Energy | 2025 |
| John Bolton ( Auto Sales) Limited | Real estate | 1955 |
| John Butler Limited | Health & social care | 2016 |
| John Edwards (North West) Limited | Construction | 2002 |
| John G Mccann Ltd | Administrative & support | 2016 |
| John Hotham Ltd | Other services | 2018 |
| John Humphreys Forensic Accounting Ltd | Professional & scientific | 2016 |
| John K Philips Developments Limited | Construction | 2006 |
| John K Philips Group Limited | Transport & logistics | 2026 |
| John Lamb Executive Solutions Ltd | Professional & scientific | 2014 |
| John Martyn Engineering Limited | Administrative & support | 2014 |
| John Oates Garage Ltd. | Wholesale & retail | 2013 |
| John Perry Limited | Professional & scientific | 2002 |
| John Scott Precision Limited | Administrative & support | 2016 |
| Johnny MAC Interiors Ltd | Administrative & support | 2020 |
| Johnson Carpenter Plus Limited | Construction | 2021 |
| Johnson Commercial Consulting Limited | Administrative & support | 2024 |
| Johnson Health and Safety Ltd | Professional & scientific | 2025 |
| Johnson Medical Ltd | Health & social care | 2026 |
| Johnson Welding Inspection Services Ltd | Administrative & support | 2024 |
| Johnsons Farm Limited | Agriculture & fishing | 2023 |
| Johnston Advisory Ltd | Professional & scientific | 2024 |
| Johnston COX Limited | Administrative & support | 2024 |
| Johnston Jones Media Ltd | Information & communication | 2018 |
| Johnyscars Limited | Wholesale & retail | 2018 |
| Joint Aviation Ventures Limited | Administrative & support | 2025 |
| Joint Civil AID Corps Limited | Public administration | 2026 |
| Joint Productions Limited | Manufacturing | 2019 |
| Jointheir Consulting Ltd | Information & communication | 2018 |
| Jojo Kids Ltd | Wholesale & retail | 2018 |
| Jojo Shop Ltd | Wholesale & retail | 2024 |
| Jojoja Ltd | Hospitality | 2020 |
| Joki Ltd | Professional & scientific | 2023 |
| JOL Engineering Limited | Administrative & support | 2013 |
| JOL Serivces Ltd | Professional & scientific | 2025 |
| Joleyns Hair & Hair Extension Specialist Ltd | Other services | 2025 |
| Jolley Holdings Ltd | Financial services | 2019 |
| Jolley Homes Limited | Real estate | 2018 |
| Jolley Investments Limited | Real estate | 2024 |
| Jolleygood Geoscience Limited | Professional & scientific | 2025 |
| Jolly Steppers Limited | Education | 2017 |
| Joloz Group Limited | Real estate | 2025 |
| JOM Civils Limited | Financial services | 2015 |
| Joma Solutions Ltd | Administrative & support | 2025 |
| JON Corbett Consultancy Ltd | Professional & scientific | 2025 |
| JON Llewellyn Limited | Administrative & support | 2025 |
| JON Thorne Draughting Services Limited | Administrative & support | 2015 |
| Jonathan Newsham Consulting Limited | Transport & logistics | 2016 |
| Jonathan Stoker Limited | Administrative & support | 2023 |
| Jones Bakeries Ltd | Manufacturing | 2024 |
| Jones Brothers Developments Ltd | Construction | 2016 |
| Jones Design Solutions Ltd | Administrative & support | 2007 |
| Jones Engineering Consultancy Limited | Construction | 2019 |
| Jones Joinery and Carpentry Ltd | Construction | 2025 |
| Joneses Developments Limited | Construction | 2023 |
| Jonestown Construction Limited | Construction | 2011 |
| Jonikad Services Limited | Hospitality | 2024 |
| Jonny Arrowsmith Limited | Real estate | 2024 |
| Jooce Marketing & PR Limited | Professional & scientific | 2009 |
| Joof Homes Limited | Construction | 2014 |
| Joof Hotels Limited | Hospitality | 2021 |
| Joof OPS Limited | Real estate | 2021 |
| Joole Site Services Ltd | Manufacturing | 2010 |
| Joown Ltd | Real estate | 2022 |
| Jordan B PT Ltd | Other services | 2025 |
| Jordan Clapham Creative Limited | Professional & scientific | 2016 |
| Jordan Timber Limited | Wholesale & retail | 1992 |
| Jordon H Entertainments Ltd | Professional & scientific | 2025 |
| Jore Homes Ltd | Real estate | 2018 |
| Jorge Ventures Limited | Wholesale & retail | 2026 |
| JOS Planning Ltd | Administrative & support | 2024 |
| Josa Procurement Limited | Professional & scientific | 2017 |
| Josan Property Ltd | Real estate | 2025 |
| Joschain Consultancy Limited | Information & communication | 2014 |
| Joseph Simpson Holiday Lets Ltd | Real estate | 2017 |
| Joseph Trainer Limited | Wholesale & retail | 2010 |
| Josh Hardy Limited | Administrative & support | 2024 |
| Joshi Projects Ltd | Administrative & support | 2023 |
| Joss Musgrave Installations Ltd | Administrative & support | 2025 |
| Joule Academy Limited | Education | 2020 |