| Jave Technologies Limited | Information & communication | 2011 |
| Javelin Express Ltd | Transport & logistics | 2008 |
| Javeria Traders Limited | Wholesale & retail | 2024 |
| Javs Srls Ltd | Hospitality | 2023 |
| Jaxx Trading Ltd | Construction | 2004 |
| JAY One Media Ltd | Administrative & support | 2022 |
| Jaymac Limited | Construction | 1997 |
| Jaymic Systems Limited | Other services | 2004 |
| Jays Reporting Ltd | Health & social care | 2020 |
| Jays U.K. Limited | Real estate | 1992 |
| Jays World Limited | Extraterritorial | 1992 |
| Jaysand Limited | Real estate | 2004 |
| Jazz Estates PVT Ltd | Real estate | 2025 |
| JB Cleaning Services (Norwich) Ltd | Administrative & support | 2013 |
| JB Commercial Limited | Hospitality | 2024 |
| JB Creative Marketing Limited | Professional & scientific | 2024 |
| JB Decorating Services (East Anglia) Limited | Construction | 2021 |
| JB Developments Worcester Limited | Real estate | 2015 |
| JB Electrical Technical Services Limited | Professional & scientific | 2020 |
| JB Express Ltd | Hospitality | 2026 |
| JB Investments & Property Company Ltd | Financial services | 2020 |
| JB LEX Limited | Professional & scientific | 2002 |
| JB Plastering Services Ltd | Construction | 2022 |
| JB Refurbishments (Staffs) Ltd | Construction | 2018 |
| JB Retail Group Limited | Wholesale & retail | 2025 |
| JB Studio Design Ltd | Professional & scientific | 2012 |
| JBA Holdings Limited | Hospitality | 2016 |
| Jbdrywall Ltd | Construction | 2024 |
| Jbe.Marketing Limited | Professional & scientific | 2018 |
| JBF Plumbing & Heating (Norfolk) Ltd | Construction | 2023 |
| Jblp 2 Limited | Hospitality | 2023 |
| JBM Electrical Services Ltd | Construction | 2018 |
| JBM Transport Limited | Transport & logistics | 2019 |
| JBP Construction Ltd | Real estate | 2022 |
| JBP Group Holdings Ltd | Financial services | 2022 |
| JBP Lettings Ltd | Real estate | 2022 |
| JBS Renewables Limited | Professional & scientific | 2024 |
| JBS Services (East) Ltd | Construction | 2023 |
| JC Bishop Investments Limited | Real estate | 2025 |
| JC Chandler Ltd | Professional & scientific | 2025 |
| JC Heron Financial Ltd | Financial services | 2015 |
| JC Kitchen & Bathrooms Ltd | Manufacturing | 2024 |
| JC Newco Limited | Administrative & support | 2005 |
| JC Rentals Ltd | Administrative & support | 2022 |
| JC Squared Property Management LLP | | 2022 |
| Jcac Limited | Financial services | 2025 |
| JCB Electrical Ltd | Construction | 2013 |
| JCC Customs & Commercials Ltd | Manufacturing | 2023 |
| JCC Refurbishments Ltd | Construction | 2014 |
| Jcct London Ltd | Hospitality | 2018 |
| JCF (SQN 2) Limited | Financial services | 2017 |
| JCF (SQN) Limited | Financial services | 2015 |
| JCF (Ssif) Limited | Financial services | 2017 |
| JCF 2025 Bonds Limited | Financial services | 2020 |
| JCG Cinematography Ltd | Professional & scientific | 2025 |
| Jchawkesconsulting Ltd | Information & communication | 2024 |
| JCI Industries Ltd | Administrative & support | 2016 |
| JCL Developments Limited | Construction | 2026 |
| JCM Planning Ltd | Information & communication | 2012 |
| JCR Property Rental Limited | Real estate | 2022 |
| JCR Tutors Ltd | Education | 2023 |
| JCS Decoration Limited | Construction | 2019 |
| Jcte Limited | Health & social care | 2010 |
| JCW31 Limited | Professional & scientific | 2012 |
| JD Actuarial Solutions Limited | Professional & scientific | 2016 |
| JD Briggs Ltd | Financial services | 2015 |
| JD Car Sales (East Anglia) Ltd | Wholesale & retail | 2024 |
| JD Catering Equipment Solutions Ltd | Manufacturing | 2006 |
| JD Commercial Catering & Refrigeration Services Limited | Manufacturing | 2020 |
| JD Consults Limited | Health & social care | 2021 |
| JD Hand Car Wash Ltd | Wholesale & retail | 2013 |
| JD Heating Services Limited | Construction | 2021 |
| JD Indian Limited | Hospitality | 2016 |
| JD Klocwork Limited | Real estate | 2014 |
| JD Plant Nursery Ltd | Agriculture & fishing | 2025 |
| JD Short Term Accommodation Limited | Hospitality | 2025 |
| JDA Plumbing and Heating Ltd | Construction | 2015 |
| Jdavila Photography Ltd | Professional & scientific | 2017 |
| JDB Assets Ltd | Financial services | 2025 |
| JDB Carpentry & Building Solutions Ltd | Construction | 2025 |
| Jdbell Services Ltd | Wholesale & retail | 2023 |
| Jdcards Ltd | Wholesale & retail | 2026 |
| JDF Financial Solutions Limited | Financial services | 2013 |
| JDH Roofing Limited | Construction | 2026 |
| Jdhm Homes Ltd | Real estate | 2025 |
| JDL Surveying Limited | Professional & scientific | 2014 |
| JDM Carpentry Ltd | Construction | 2017 |
| Jdma Group Limited | Construction | 2023 |
| Jdma Paving and Landscaping Limited | Construction | 2015 |
| JDN Brickwork Limited | Construction | 2020 |
| Jdrey Multipurpose Venture Ltd | Wholesale & retail | 2026 |
| JDS Services Limited | Construction | 2005 |
| JDT Music Academy Limited | Education | 2019 |
| Jdworks Ltd | Manufacturing | 2025 |
| JE Nominees Limited | Extraterritorial | 2013 |
| Jeanius Ltd | Extraterritorial | 2011 |
| Jebj Investments | Financial services | 2019 |
| Jeckells & SON Limited | Manufacturing | 1927 |
| JED Food Technical Ltd | Professional & scientific | 2021 |
| Jedi Heating Ltd | Construction | 2024 |