| J.J Driving Solutions Limited | Transport & logistics | 2020 |
| J.R UK Property Limited | Real estate | 2018 |
| J.R.Stone Ltd | Construction | 2011 |
| J.Star Travel Ltd | Transport & logistics | 2023 |
| J2K Properties Ltd | Real estate | 2021 |
| J3 Marquees Limited | Administrative & support | 2024 |
| J3JR LLP | | 2006 |
| J@A Trading Limited | Wholesale & retail | 2023 |
| Jaan & Quickfit Ltd | Wholesale & retail | 2019 |
| JAB Tropical Ltd | Wholesale & retail | 2021 |
| Jabal Holdings Ltd | Financial services | 2025 |
| JAC Real Estate Ltd | Real estate | 2023 |
| Jack's Garden Store Limited | Wholesale & retail | 2009 |
| Jacksons Goods Ltd | Wholesale & retail | 2025 |
| Jade Motors UK Limited | Wholesale & retail | 2025 |
| Jads Vedi Properties Limited | Real estate | 2024 |
| JAF International Limited | Other services | 2020 |
| Jaferytech Limited | Wholesale & retail | 2025 |
| Jaff Development Ltd | Construction | 2025 |
| Jaflelah Holding Ltd | Construction | 2025 |
| Jafri Limited | Other services | 2022 |
| JAG Construction Services Ltd | Construction | 2016 |
| JAG Invest Limited | Real estate | 2024 |
| JAG Sangha Ltd | Health & social care | 2025 |
| Jagdeep Construction Ltd | Construction | 2018 |
| Jagga Transport Ltd | Transport & logistics | 2024 |
| Jaggi Construction Ltd | Construction | 2020 |
| Jagjeet Singh Construction Ltd | Construction | 2021 |
| Jagjeet Singh Ltd | Construction | 2021 |
| Jagpal Singh Ltd | Construction | 2025 |
| Jagtar Transport Limited | Transport & logistics | 2025 |
| Jaguar Electrics Limited | Construction | 2021 |
| Jagvir Singh Ltd | Construction | 2024 |
| JAI MAA Lakshmi Mata Limited | Real estate | 2018 |
| JAI Shree SAI Ltd | Construction | 2024 |
| Jaib's Automation & Metal Work Ltd | Manufacturing | 2024 |
| Jain Estates Limited | Real estate | 2013 |
| Jain Global Holdings Limited | Wholesale & retail | 2021 |
| Jain Group Berkshire Ltd | Real estate | 2023 |
| Jain Group Holdings Ltd | Financial services | 2018 |
| Jainco (UK) Limited | Wholesale & retail | 2004 |
| JAK Ventures Limited | Real estate | 2024 |
| Jakani Consulting Limited | Information & communication | 2019 |
| Jake Management Services Ltd | Construction | 2018 |
| Jamal Sons Limited | Professional & scientific | 2013 |
| Jambo Cargo Limited | Transport & logistics | 2016 |
| Jamhealthcare Ltd | Public administration | 2025 |
| Jammu & Sons Ltd | Construction | 2018 |
| Jammu Construction Ltd | Construction | 2020 |
| JAN & Co Property Limited | Real estate | 2024 |
| JAN Sher Limited | Real estate | 2022 |
| Janar and Sons Ltd | Real estate | 2017 |
| Janecosmetics Ltd | Wholesale & retail | 2024 |
| Jangoo Limited | Wholesale & retail | 2025 |
| Jankee Ltd | Manufacturing | 2026 |
| Janspur Limited | Construction | 2012 |
| Janus House Ltd | Real estate | 2021 |
| JAO Distributions Ltd | Wholesale & retail | 2026 |
| JAP Build Ltd | Construction | 2025 |
| JAP Builder Limited | Construction | 2025 |
| JAP Cleaning Ltd | Administrative & support | 2026 |
| JAP Food & Wine Ltd | Wholesale & retail | 2017 |
| JAP Roofing Contractors Limited | Construction | 2020 |
| Jap&Tan Limited | Wholesale & retail | 2024 |
| Japji and Fateh Limited | Real estate | 2021 |
| Japji Auto Ltd | Wholesale & retail | 2017 |
| Japji INT Ltd | Construction | 2026 |
| Japleen Enterprises Ltd | Wholesale & retail | 2009 |
| Japp Financial Ltd | Financial services | 2021 |
| JAR Contractors Ltd | Construction | 2025 |
| Jariamoss Ltd | Hospitality | 2024 |
| Jarjar Trade Ltd | Wholesale & retail | 2024 |
| Jarrow Gate Digital Limited | Professional & scientific | 2025 |
| JAS & DIL Convenience Store Ltd | Wholesale & retail | 2024 |
| JAS & DIL Investments Ltd | Real estate | 2025 |
| JAS & JAS Properties Limited | Real estate | 2025 |
| JAS 1 Builders Ltd | Construction | 2018 |
| JAS Builder (Hayes) Ltd | Construction | 2025 |
| JAS U.K. Ltd | Other services | 2017 |
| Jasa Shopfront & Shutters Ltd | Construction | 2018 |
| Jase Services Ltd | Information & communication | 2024 |
| Jasee Hire Car Ltd | Administrative & support | 2022 |
| Jasgur Services Limited | Transport & logistics | 2019 |
| Jaskiran Limited | Professional & scientific | 2025 |
| Jaskirat Ltd | Construction | 2025 |
| Jasleen Coaching Ltd | Professional & scientific | 2025 |
| Jasmeet Properties Ltd | Real estate | 2024 |
| Jasmin Food & Wine Ltd | Wholesale & retail | 2025 |
| Jasnag Limited | Health & social care | 2022 |
| Jason Mayo Consultancy Limited | Professional & scientific | 2016 |
| Jason Renovations Ltd | Construction | 2021 |
| Jasoor Launderette Ltd | Other services | 2022 |
| Jaspal SINGH2 Ltd | Construction | 2025 |
| Jass Bhatti Ltd | Construction | 2024 |
| JASS24 Truck Tyres Ltd | Transport & logistics | 2019 |
| Jassa Properties Ltd | Real estate | 2025 |
| Jassa Top Transport Ltd | Transport & logistics | 2025 |
| Jassaircon Limited | Construction | 2026 |
| Jassi Builders Ltd | Construction | 2016 |
| Jassi Construction Ltd | Construction | 2016 |