| Investments M&M Ltd | Real estate | 2023 |
| Invictus Healthcare Solutions Limited | Health & social care | 2025 |
| Invictus Innovations Limited | Information & communication | 2022 |
| Invictus Living Ltd | Real estate | 2026 |
| Invictus Property Network Ltd | Administrative & support | 2026 |
| Iotp(Uk) Ltd | Administrative & support | 2025 |
| IP Insolvency Limited | Financial services | 2020 |
| Ipcctv.Tech Ltd | Construction | 2025 |
| IPI Global Solutions LLP | | 2020 |
| Iqbal Equity Ltd | Real estate | 2020 |
| Isaac James Consulting Ltd | Administrative & support | 2026 |
| Isaac Mark Limited | Wholesale & retail | 2024 |
| ISAIAH43 Ltd | Transport & logistics | 2025 |
| Ishaq Properties Ltd | Real estate | 2024 |
| Isher Parkash Holdings Ltd | Financial services | 2024 |
| Isleblaque Ltd | Other services | 2025 |
| ISO100 Ltd | Professional & scientific | 2020 |
| Israel N Sons Limited | Transport & logistics | 2025 |
| Itacof Limited | Professional & scientific | 2020 |
| Itan Transport Limited | Transport & logistics | 2019 |
| Itchen Stoke Limited | Wholesale & retail | 2017 |
| Itec Select Limited | Administrative & support | 2014 |
| Itibari Limited | Professional & scientific | 2017 |
| Itzholdings Limited | Financial services | 2025 |
| IVY Jewellers Birmingham Limited | Manufacturing | 2023 |
| Ixion Holdings (Contracts) Limited | Administrative & support | 2009 |
| Iyuno Holding I UK Limited | Information & communication | 2004 |
| Iyuno Holding II UK Limited | Information & communication | 1990 |
| Iyuno UK II Ltd. | Information & communication | 2013 |
| Iyuno UK Ltd. | Information & communication | 2004 |
| Iyuno UK V Limited | Information & communication | 1988 |
| J & K Building & Maintenance Ltd | Construction | 2020 |
| J & R Specialist Cars Ltd | Wholesale & retail | 2018 |
| J & SON Pubs Limited | Hospitality | 2017 |
| J and 2A Ltd | Wholesale & retail | 2026 |
| J Basra Ltd | Construction | 2024 |
| J Johal Properties Limited | Real estate | 2013 |
| J P Bates Limited | Professional & scientific | 2014 |
| J S Construction Consultant Ltd | Construction | 2025 |
| J S Golden Courier Limited | Transport & logistics | 2025 |
| J Singh Consulting Ltd | Information & communication | 2025 |
| J&D UK Immigration Services Ltd. | Professional & scientific | 2015 |
| J&D Workforce Management & Compliance Limited | Information & communication | 2024 |
| J&J Consultants Ltd | Information & communication | 2023 |
| J&J Couriers Ltd | Transport & logistics | 2019 |
| J&J Shopfronts Ltd | Administrative & support | 2010 |
| J&L Installations Limited | Construction | 2013 |
| J&M Shopping Ltd | Wholesale & retail | 2020 |
| J&N Orchard Homes Ltd | Real estate | 2025 |
| J. & P. Lewis(Metals) Holdings Limited | Administrative & support | 2021 |
| J. & P. Lewis(Metals)Limited | Water & waste | 1965 |
| J. Alex Eton Ltd | Wholesale & retail | 2025 |
| J. Docter Limited | Wholesale & retail | 2000 |
| J.D. Neuhaus Limited | Wholesale & retail | 1998 |
| J.L. COX (Cranes) Limited | Administrative & support | 1989 |
| J.O. Medical Services Ltd | Health & social care | 2023 |
| J.O.J.A. Limited | Transport & logistics | 2017 |
| J.R .Strategic Operations Ltd | Professional & scientific | 2026 |
| J4 OHL Consultancy Limited | Information & communication | 2007 |
| JA Bhatti Ltd | Real estate | 2026 |
| Jaap Group Ltd | Wholesale & retail | 2021 |
| Jabo Trans Ltd | Transport & logistics | 2018 |
| Jackson LEE Stephen Limited | Wholesale & retail | 2023 |
| Jacos Investments Ltd | Real estate | 2021 |
| Jagg Construction Ltd | Construction | 2013 |
| Jahn Housing & Support Ltd | Real estate | 2024 |
| JAI Santhoshima Ltd | Professional & scientific | 2019 |
| Jake Hadley MMA Ltd | Arts & recreation | 2026 |
| James Freeman Autodoc Ltd | Manufacturing | 2024 |
| James NDE Drive Ltd | Transport & logistics | 2016 |
| Jammu Transport Limited | Transport & logistics | 2023 |
| Japanese Auto Trade & Transport Ltd | Wholesale & retail | 2022 |
| Japji Construction U.K. Ltd | Construction | 2024 |
| JAS Services Ltd | Transport & logistics | 2020 |
| Jasmine Publications Limited | Information & communication | 2019 |
| Jasssukh Construction Ltd | Administrative & support | 2022 |
| Jaswal Constructions Ltd | Construction | 2016 |
| Jaswal Developments Ltd | Real estate | 2023 |
| Jaswal Home Improvement Ltd | Construction | 2022 |
| Jaswal Housing Ltd | Real estate | 2026 |
| Jaswant Construction Limited | Construction | 2017 |
| JAV Developments Limited | Construction | 2015 |
| JAY Sparkles Limited | Administrative & support | 2025 |
| JAY Tech Consulting Ltd | Information & communication | 2025 |
| Jay's Valeting Ltd | Administrative & support | 2022 |
| Jayz Ltd | Transport & logistics | 2013 |
| Jbhd Ltd | Professional & scientific | 2016 |
| JC Apex Ltd | Education | 2025 |
| JD Mobile Ltd | Wholesale & retail | 2021 |
| Jeamda Limited | Health & social care | 2023 |
| Jegu Trans Ltd | Transport & logistics | 2017 |
| Jern W Limited | Financial services | 2024 |
| Jess Pharma Ltd | Health & social care | 2020 |
| Jesus Only Ltd | Wholesale & retail | 2025 |
| Jetman UK Ltd | Wholesale & retail | 2019 |
| JFH Media Limited | Information & communication | 2022 |
| JG P1 Limited | Real estate | 2025 |
| Jgks Construction Ltd | Construction | 2024 |
| JHJ Technology Ltd | Information & communication | 2020 |
| JIN HUA Limited | Hospitality | 2026 |