| Jose Construction Ltd | Construction | 2019 |
| Jose Olivio Borges Moreno Ltd | Extraterritorial | 2022 |
| Joseph Adamson (Europe) Limited | Manufacturing | 1943 |
| Joseph Brisark Ltd | Real estate | 2019 |
| Joseph Carpentry Limited | Manufacturing | 2025 |
| Joseph Hughes Associates Limited | Administrative & support | 2020 |
| Joseph Paul Associates Limited | Professional & scientific | 2020 |
| Joseph Search Limited | Administrative & support | 2016 |
| Josh Perrett Plastering Ltd | Construction | 2020 |
| Josh Punchard Ltd | Transport & logistics | 2021 |
| Joshi Urology Care Limited | Health & social care | 2018 |
| Joshua Clark Business Services Limited | Professional & scientific | 2015 |
| Joshua Daniel Properties Ltd | Real estate | 2023 |
| Joshua Developments Ltd | Construction | 2010 |
| Joshua Hanson Limited | Wholesale & retail | 2025 |
| Joshua Reeds Limited | Extraterritorial | 2026 |
| JOSHUA12 Global Ltd | Extraterritorial | 2018 |
| Josi and MAT Cozy Home Limited | Financial services | 2025 |
| Josiah Wedgwood & Sons Limited | Manufacturing | 1958 |
| Joson Ltd | Wholesale & retail | 2026 |
| Jospic Enterprises Ltd. | Real estate | 2019 |
| Joss Service Ltd | Transport & logistics | 2022 |
| Josua Hinchly Online Ltd | Wholesale & retail | 2024 |
| JOT Global Resources Ltd | Wholesale & retail | 2025 |
| Jotajrservices Ltd | Wholesale & retail | 2024 |
| Joteco Holdings Ltd | Financial services | 2019 |
| Jotham Lois Healthcare Ltd | Wholesale & retail | 2019 |
| Jotranet Limited | Information & communication | 2025 |
| Jottnar Ltd | Manufacturing | 2011 |
| Joudai Ltd | Wholesale & retail | 2024 |
| Jouissance Ltd | Professional & scientific | 2017 |
| Journey Juice Ltd | Manufacturing | 2019 |
| Journey of Diverse Means Services Limited | Wholesale & retail | 2025 |
| Journolink Limited | Administrative & support | 2013 |
| Jova Limited | Administrative & support | 2017 |
| Joveo Ltd | Information & communication | 2019 |
| Jovi Creative Ltd | Arts & recreation | 2018 |
| Jovialink International PC | | 2021 |
| Jovic Consulting Ltd | Professional & scientific | 2015 |
| Joy Book W Ltd | Agriculture & fishing | 2021 |
| Joy Designers Global Ltd | Information & communication | 2025 |
| Joy Unlimited Limited | Professional & scientific | 2017 |
| Joyaux Ltd | Wholesale & retail | 2015 |
| Joybaby Education Limited | Education | 2024 |
| Joyful Solutions Limited | Administrative & support | 2017 |
| Joyomas Ltd | Wholesale & retail | 2025 |
| Joyomyoga Ltd | Other services | 2021 |
| Joys Development Limited | Professional & scientific | 2014 |
| Joysbio Biotechnology Co., Ltd | Extraterritorial | 2020 |
| Joytastic Ltd | Extraterritorial | 2021 |
| JP Acquisitions Limited | Real estate | 2017 |
| JP and Group Ltd | Administrative & support | 2017 |
| JP Auto Traders Ltd | Wholesale & retail | 2025 |
| JP Barber Company Ltd | Other services | 2023 |
| JP Building & Maintenance Ltd | Construction | 2021 |
| JP Capital Management Ltd | Wholesale & retail | 2018 |
| JP Catering Limited | Hospitality | 2024 |
| JP Executive Lettings & Sales Limited | Real estate | 2013 |
| JP Ground & Developments Limited | Construction | 2025 |
| JP Inspire Consultancy Ltd | Professional & scientific | 2014 |
| JP Private Clients 2019 LLP | | 2019 |
| JP Private Clients Limited | Financial services | 2015 |
| JP Property Investment Group Limited | Real estate | 2020 |
| JP Thomas Ltd | Other services | 2019 |
| JP Trading Solution Ltd | Construction | 2019 |
| JP Traffic Ltd | Wholesale & retail | 2021 |
| JP Windle LLP | | 2025 |
| JP Window Cleaners Ltd | Administrative & support | 2010 |
| Jp's Quality Service Ltd | Manufacturing | 2009 |
| Jp-Ss (Holdings) Apec Ltd | Financial services | 2021 |
| JP3 Properties Limited | Real estate | 2025 |
| JPA & QF Ltd | Real estate | 2023 |
| Jpaml Solutions Ltd | Professional & scientific | 2016 |
| Jpbtradings Limited | Financial services | 2025 |
| JPD Media Limited | Professional & scientific | 2007 |
| Jpea Limited | Professional & scientific | 2014 |
| JPF Leisure Sales Limited | Wholesale & retail | 2026 |
| JPG Driver Hire Ltd | Transport & logistics | 2025 |
| JPG Refrigeration & Electrical Services Ltd | Manufacturing | 2017 |
| JPG Staff (UK) Ltd | Financial services | 2020 |
| JPI Motors Ltd | Wholesale & retail | 2021 |
| Jpingke Trade Ltd | Wholesale & retail | 2025 |
| JPJ Homes Limited | Real estate | 2023 |
| JPL Taxi Services Limited | Wholesale & retail | 2018 |
| Jplasset Ltd | Hospitality | 2019 |
| JPM Constructions (London) Ltd | Construction | 2020 |
| Jpma Surveyors Ltd | Professional & scientific | 2023 |
| Jpmg Financial Solutions Limited | Professional & scientific | 2020 |
| Jpmg Solutions Ltd | Administrative & support | 2017 |
| JPO Solutions Ltd | Information & communication | 2010 |
| JPR Carpentry and Building Services Ltd | Construction | 2024 |
| JPR Holdings Group Ltd | Financial services | 2025 |
| JPR Legal Consultant Limited | Professional & scientific | 2025 |
| JPR Railway Operational Cable Consultancy Service Ltd | Construction | 2021 |
| JPS Consults Limited | Administrative & support | 2026 |
| JPS Global Consulting Ltd | Information & communication | 2013 |
| JPS Heating Solutions Limited | Manufacturing | 2025 |
| JPS Holdings (Cardiff) Limited | Real estate | 2023 |
| JPS Homes (Cardiff) Limited | Households | 2017 |
| JPS Services (South) Ltd | Construction | 2011 |