| JDF Farms Holdings Limited | Financial services | 2020 |
| JDF Farms LLP | | 2010 |
| JDG Commercials Limited | Wholesale & retail | 2005 |
| JDG Holdings Limited | Administrative & support | 2017 |
| JDH Photography Ltd | Professional & scientific | 2013 |
| Jdholmes Ltd | Health & social care | 2023 |
| Jdjsh Ltd | Wholesale & retail | 2024 |
| JDL Enterprises Limited | Information & communication | 2017 |
| JDM Motors Ltd | Wholesale & retail | 2024 |
| JDM Sheff Ltd | Extraterritorial | 2025 |
| JDM Trading Limited | Wholesale & retail | 2019 |
| JDM Transport Ltd | Transport & logistics | 2021 |
| JDR Car Sales Ltd | Wholesale & retail | 2023 |
| JDS Group Limited | Wholesale & retail | 2025 |
| JDS Windows Limited | Construction | 2021 |
| Jdutton Properties Ltd | Real estate | 2025 |
| Jeanieiq Limited | Information & communication | 2026 |
| JED Holdings Ltd | Real estate | 2017 |
| Jeff Cook Design Limited | Information & communication | 2017 |
| Jeff Cooper Controls Limited | Manufacturing | 2008 |
| Jefferson Asset Management Ltd | Professional & scientific | 2012 |
| Jefferson Decorators Ltd | Construction | 2025 |
| JEG Property Lets Ltd | Real estate | 2023 |
| JEL Construction Limited | Construction | 2018 |
| Jemima Belle Ltd | Real estate | 2002 |
| Jenetex Limited | Manufacturing | 2001 |
| Jenkinson & Co (Holdings) Limited | Professional & scientific | 1999 |
| Jenkinson & Co (Properties) Ltd | Real estate | 2002 |
| Jenkinson & Co Limited | Financial services | 1999 |
| Jenkinson and Co (CV) Ltd | Financial services | 2018 |
| Jenkinson Consulting Limited | Professional & scientific | 2024 |
| Jennie's Pet Care Services Limited | Professional & scientific | 2025 |
| Jennings Groundworks Limited | Construction | 2017 |
| Jenvy Ltd | Manufacturing | 2022 |
| Jephinias Ltd | Transport & logistics | 2024 |
| Jermy Properties Limited | Real estate | 2025 |
| Jester Management Ltd | Professional & scientific | 2025 |
| Jeston Properties Limited | Real estate | 1976 |
| Jesus Christ Compassion Ministries Int'L Ltd | Other services | 2025 |
| Jete Automotive Ltd | Wholesale & retail | 2024 |
| Jetski Worldwide Ltd | Arts & recreation | 2022 |
| Jetwash and Hose Manufacturing Limited | Wholesale & retail | 2014 |
| Jewel Fire Group Limited | Manufacturing | 1990 |
| Jewel Fire Holdings Limited | Manufacturing | 2025 |
| Jewel Fire Products (UK) Ltd | Manufacturing | 2007 |
| Jewel Plant Services Ltd | Wholesale & retail | 2015 |
| Jewitt's Joinery Rotherham Limited | Construction | 2003 |
| JFB Reinstatement Ltd | Construction | 2022 |
| JFS (Holdings) Limited | Extraterritorial | 2014 |
| JG Haulage Ltd | Transport & logistics | 2013 |
| JG Systems Limited | Construction | 2025 |
| JGM Access Limited | Construction | 2015 |
| JGR Group Ltd | Wholesale & retail | 2021 |
| JH Baits Ltd | Manufacturing | 2020 |
| JH Drive Ltd | Transport & logistics | 2026 |
| JH Recycling Ltd | Manufacturing | 2022 |
| JHB Security Limited | Administrative & support | 2022 |
| JHK Civils & Drainage Ltd | Construction | 2022 |
| JHR Physio Ltd | Transport & logistics | 2014 |
| JIM Bateman Consulting Limited | Professional & scientific | 2013 |
| Jitz Care Ltd | Health & social care | 2025 |
| JJ Gardening Services Ltd | Administrative & support | 2016 |
| JJ Management Consultants Limited | Professional & scientific | 2011 |
| JJ Tyres and Exhausts Limited | Wholesale & retail | 2013 |
| Jj's Chip Shop Ltd | Hospitality | 2018 |
| Jj's PUB Co Ltd | Hospitality | 2026 |
| JJD Consultancy Services Limited | Professional & scientific | 2011 |
| JJESTATES9 Ltd | Real estate | 2023 |
| JJI Testing Ltd | Information & communication | 2024 |
| JJJ Group Ltd | Wholesale & retail | 2019 |
| JJL Waste Consultancy Limited | Water & waste | 2017 |
| JJP Door Solutions Limited | Manufacturing | 2017 |
| Jjpokevault Ltd | Wholesale & retail | 2026 |
| JJW Apps Ltd | Information & communication | 2026 |
| JK Walker Mortgage Services Ltd | Financial services | 2023 |
| JKA Motors Limited | Wholesale & retail | 2017 |
| JKH & Partners Ltd | Administrative & support | 2024 |
| JKP Engineering (UK) Ltd | Manufacturing | 2002 |
| JKV Trading Ltd | Wholesale & retail | 2022 |
| JL Property Rentals Limited | Real estate | 2018 |
| JL Recycling Ltd | Wholesale & retail | 2022 |
| JL Services Yorkshire Ltd | Construction | 2022 |
| Jlad Marketing Limited | Wholesale & retail | 2025 |
| Jlad Real Estate Limited | Real estate | 2025 |
| JLB Interiors Ltd | Construction | 2020 |
| JLC Autos Limited | Wholesale & retail | 2022 |
| JLC Developments Ltd | Construction | 2018 |
| JLC Properties 2021 Limited | Real estate | 2024 |
| JLC Property Investments Ltd | Households | 2026 |
| JLH PAT Testing Ltd | Construction | 2026 |
| JLH Properties Manchester Ltd | Real estate | 2026 |
| JLH Properties South Yorkshire Ltd | Real estate | 2024 |
| JLM Lettings Ltd | Real estate | 2024 |
| JLM Real Estate Group Limited | Real estate | 2022 |
| JLP Joinery Limited | Construction | 2025 |
| JLP Properties (Yorkshire) Ltd | Real estate | 2026 |
| JLR Fireproofing Limited | Construction | 2022 |
| JLW Passive Fire Protection Limited | Construction | 2017 |
| JM Badesha Logistics Ltd | Transport & logistics | 2024 |
| JM Electrical (Yorkshire) Ltd | Construction | 2024 |