| Jaspa.Io Ltd | Information & communication | 2017 |
| Jasper a Limited | Hospitality | 2020 |
| JASVIRKAUR05 Ltd | Hospitality | 2026 |
| JAY C Products Limited | Wholesale & retail | 2015 |
| Jayhawk Worldwide Limited | Real estate | 2025 |
| JAZ ALI Ltd | Health & social care | 2021 |
| Jazz Line Ventures Ltd | Financial services | 2025 |
| JB Advanced Windows and Doors Ltd | Construction | 2020 |
| JB Architectural Ltd | Professional & scientific | 2022 |
| JB Dressmakers Limited | Manufacturing | 2019 |
| JB York Limited | Construction | 2013 |
| Jbarnett Consulting Ltd | Professional & scientific | 2025 |
| Jbekks Ltd | Agriculture & fishing | 2014 |
| JBM Holdings Limited | Financial services | 2018 |
| JC & RM Bloom Limited | Agriculture & fishing | 2023 |
| JC DB Solutions Limited | Information & communication | 2026 |
| JC Estates (Selby) Limited | Real estate | 2016 |
| JC Intelligence Solutions Limited | Other services | 2025 |
| JC Landscaping Ltd | Administrative & support | 2023 |
| JC Poultry Limited | Agriculture & fishing | 2019 |
| JC Yorkshire Roofing and Repairs Ltd | Construction | 2025 |
| Jc-It Solutions Limited | Information & communication | 2011 |
| JCA York Limited | Wholesale & retail | 2024 |
| JCB Automotive Limited | Wholesale & retail | 2024 |
| JCG Property Lets Ltd | Hospitality | 2018 |
| JCJ Design and Construction Limited | Administrative & support | 2009 |
| Jckalmeida Ltd | Transport & logistics | 2025 |
| JCM Contractors Ltd | Construction | 2017 |
| JCM Solutions 11 Ltd | Manufacturing | 2016 |
| Jcpt Investments Limited | Real estate | 2025 |
| JCS Aeroengineering Ltd | Professional & scientific | 2025 |
| JCT Contractors (York) Ltd | Manufacturing | 2024 |
| JCW Electric Ltd | Manufacturing | 2024 |
| JCW Investments Ltd | Real estate | 2004 |
| JD (York) Limited | Transport & logistics | 1964 |
| JD Enterprise (York) Ltd | Construction | 2021 |
| JD Landscapes (York) Ltd | Administrative & support | 2026 |
| JD Parks Limited | Hospitality | 2026 |
| JD Plant (York) Ltd | Administrative & support | 2022 |
| JD Property Management Real Estate Limited | Real estate | 2024 |
| Jd.Design&Develop Ltd | Construction | 2022 |
| JDA Property Investment Ltd | Real estate | 2024 |
| JDB Dental Limited | Health & social care | 2025 |
| JDB National Limited | Professional & scientific | 2024 |
| JDB Transport Ltd | Transport & logistics | 2003 |
| Jdhunt Ltd | Professional & scientific | 2025 |
| JDL Holdings Limited | Real estate | 2018 |
| JDL Roofing Ltd | Construction | 2020 |
| JDM Property Group Ltd | Hospitality | 2022 |
| JDM Shop Projects Limited | Construction | 2024 |
| Jdnrecycling Ltd | Water & waste | 2024 |
| Jdnt Renovations Ltd | Construction | 2021 |
| JDS York Ltd | Transport & logistics | 2019 |
| Jdspeck Limited | Construction | 2020 |
| JDV (York) Ltd | Wholesale & retail | 2007 |
| Jean Peters Limited | Other services | 2004 |
| Jean Rose Limited | Real estate | 2025 |
| JED Estates Limited | Construction | 2019 |
| Jeff Boocock Livestock Limited | Agriculture & fishing | 2025 |
| Jeff Carr Management Limited | Construction | 2023 |
| Jefferson Oak Framing and Joinery Limited | Construction | 2026 |
| Jeffersons Decorators Ltd | Construction | 2008 |
| JEL Holdings Ltd | Financial services | 2022 |
| Jelliag Limited | Real estate | 2003 |
| Jelling Dragon Limited | Wholesale & retail | 2014 |
| Jelly Crunch Media Ltd | Information & communication | 2023 |
| JEM and JAZ Ltd | Wholesale & retail | 2025 |
| JEM UK Properties Ltd | Real estate | 2022 |
| Jemkey Services Limited | Financial services | 2020 |
| Jems Hairdressing Ltd | Other services | 2017 |
| Jenix Technologies Ltd | Information & communication | 2020 |
| Jenleigh Limited | Hospitality | 2025 |
| Jenna Leanne Taylor Ltd | Extraterritorial | 2025 |
| Jennie Roberts Ltd | Professional & scientific | 2014 |
| Jennings Media Limited | Professional & scientific | 2023 |
| Jennings Power Systems Ltd | Professional & scientific | 2019 |
| Jenson Studio Colour Limited | Manufacturing | 2001 |
| Jeopardy Hospitality Limited | Hospitality | 2025 |
| Jerfro Barnsley Limited | Wholesale & retail | 2022 |
| Jess Bell Ltd | Professional & scientific | 2020 |
| Jess Geen Limited | Professional & scientific | 2017 |
| Jessica Kathryn Interiors Limited | Professional & scientific | 2025 |
| Jessika Kitchen Ltd | Hospitality | 2023 |
| JET Beauty Ltd | Other services | 2025 |
| JET Medical Flights Ltd | Health & social care | 2014 |
| JET Software Ltd | Information & communication | 2025 |
| Jetscreen ( York) Limited | Manufacturing | 2003 |
| Jetscreen Ltd | Other services | 2011 |
| Jewels Limited | Extraterritorial | 2004 |
| JG58 Limited | Real estate | 2018 |
| JGH Consultancy Limited | Financial services | 2018 |
| JGO Decorators Ltd | Construction | 2023 |
| JGS Accountancy Ltd | Professional & scientific | 2020 |
| Jgtg Enterprises Limited | Health & social care | 2025 |
| JGV Customs Ltd | Professional & scientific | 2023 |
| Jha.Lab Limited | Hospitality | 2023 |
| Jhallcatering Ltd | Hospitality | 2026 |
| Jhas' Stay Limited | Hospitality | 2026 |
| JHC Sustainability Limited | Professional & scientific | 2019 |
| JHI Properties (York) Ltd | Construction | 2022 |