| JHK Oilfield Products Ltd | Manufacturing | 2013 |
| JHP & CHH Investments | Real estate | 2024 |
| JHP (2012) Trustee Investments | Financial services | 2014 |
| JHP Investments | Financial services | 2014 |
| JHP Joinery Ltd | Construction | 2012 |
| JHR Holdings Limited | Financial services | 2022 |
| JHU Property Ltd | Real estate | 2025 |
| Jigsaw 2020 Ltd | Professional & scientific | 2020 |
| Jigsaw Coastal Ltd | Real estate | 2024 |
| Jiguo Europe Ltd | Administrative & support | 2016 |
| Jill's Unisex Hair Salon Ltd | Other services | 2024 |
| JIM Gordon Joinery Limited | Construction | 2022 |
| JIM Macfadyen Consulting Limited | Administrative & support | 2005 |
| Jimmy Macks Street Kitchen Ltd | Hospitality | 2024 |
| Jinky Services Limited | Wholesale & retail | 2014 |
| Jinnah Restaurant (Bradford) Limited | Extraterritorial | 2025 |
| Jinnah Restaurant (Leeds Road) LLP | | 2025 |
| Jinnah Restaurant (Malton) LLP | | 2019 |
| Jinnah Restaurant (Selby) LLP | | 2011 |
| Jinnah Restaurant Limited | Hospitality | 2001 |
| Jive Designs Ltd | Extraterritorial | 2013 |
| JJ (York) Warehouse Limited | Real estate | 2024 |
| JJ Hospitality Ltd | Hospitality | 2017 |
| JJ Property Consultants Limited | Professional & scientific | 2015 |
| JJ Service Accomodation Ltd | Hospitality | 2024 |
| Jjal Consulting Services Ltd | Professional & scientific | 2022 |
| JJB Agencies Ltd | Wholesale & retail | 2019 |
| Jjdc Group Limited | Wholesale & retail | 2025 |
| Jjhs Consulting Ltd | Information & communication | 2015 |
| JJR Consulting Services Ltd | Professional & scientific | 2015 |
| JJS Education Services Limited | Education | 2018 |
| Jjsn Holdings Limited | Construction | 2020 |
| JJW Coaching Limited | Other services | 2023 |
| Jjyork Ltd | Hospitality | 2018 |
| JK & MT Property Ltd | Real estate | 2012 |
| JK Harrison Ltd | Hospitality | 2021 |
| JK Personal LLP | | 2023 |
| JK Wake Properties Ltd | Real estate | 2024 |
| JKB Management Services Ltd | Professional & scientific | 2018 |
| JKR Group Ltd | Information & communication | 2019 |
| JL Fire Management Ltd | Manufacturing | 2015 |
| JL Outsourced Services Ltd | Administrative & support | 2025 |
| JLB M&A Practice Ltd | Professional & scientific | 2024 |
| JLC Brands Ltd | Wholesale & retail | 2019 |
| JLC Media Productions Ltd | Manufacturing | 2019 |
| JLD Aviation Ltd | Financial services | 2015 |
| Jliput Ltd | Health & social care | 2015 |
| JLM Plumbing Services Limited | Construction | 2021 |
| JLM Property Investments Ltd | Real estate | 2014 |
| JLR Developments ( York ) Ltd | Real estate | 2026 |
| JLR Roofing (York) Ltd | Construction | 2022 |
| JLS PEN & INK Ltd | Professional & scientific | 2021 |
| JM Accountacy Ltd | Professional & scientific | 2018 |
| JM Jewellery Ltd | Wholesale & retail | 2014 |
| JM Pickering Plant Ltd | Administrative & support | 2024 |
| JM Retail Oriel Ltd | Wholesale & retail | 2025 |
| Jmark Construction Limited | Construction | 2007 |
| Jmcmullen Consultancy Ltd | Professional & scientific | 2025 |
| JMD Railtech Limited | Information & communication | 2012 |
| JME Consultants Ltd | Professional & scientific | 2019 |
| JMI Holdings (York) Ltd | Administrative & support | 2024 |
| Jmjd Properties Ltd | Real estate | 2025 |
| JMK Transport Services Ltd | Transport & logistics | 2013 |
| JMM Automotive Ltd | Wholesale & retail | 2018 |
| JMP Yorkshire Ltd | Construction | 2015 |
| Jmpickering Property Limited | Real estate | 2023 |
| JMS (Yorkshire) Solutions Limited | Professional & scientific | 2024 |
| JMS Medical Writing Services Ltd | Professional & scientific | 2017 |
| JMS Property Group Limited | Real estate | 2023 |
| JMV Sound Ltd | Information & communication | 2025 |
| JN Consultancy Limited | Professional & scientific | 2012 |
| JN Painting & Decorating Limited | Construction | 2019 |
| JNJ Projects Ltd | Manufacturing | 2021 |
| JNM Events Limited | Manufacturing | 2008 |
| JNP (Residential Lettings) Limited | Real estate | 2001 |
| JNP (Surveyors) Limited | Administrative & support | 2000 |
| JNP Estate Agents (Princes Risborough) Limited | Real estate | 2000 |
| JNP Estate Agents Limited | Real estate | 1999 |
| JNP York Ltd | Construction | 2025 |
| Jo.P. Communications Ltd | Administrative & support | 2009 |
| Joanda Ltd | Transport & logistics | 2021 |
| Joannapropertyyork Ltd | Real estate | 2022 |
| Jobgs Ltd | Other services | 2010 |
| Jodie MB Ltd | Administrative & support | 2022 |
| JOE Bloggs Limited | Extraterritorial | 2019 |
| JOE Dallin GAS Fitting Ltd | Construction | 2020 |
| JOE Dallin Property Management Ltd | Real estate | 2026 |
| JOE Davis York Ltd | Financial services | 2026 |
| JOE Dodsworth LLP | | 2009 |
| JOE Gough Valeting Limited | Other services | 2018 |
| JOE Rooke Actor Ltd | Professional & scientific | 2022 |
| Joel Aero Consultancy Limited | Professional & scientific | 2023 |
| John Brighton Limited | Professional & scientific | 2018 |
| John Burley (Investments) Limited | Real estate | 1951 |
| John Drury & SON Coal Ltd | Wholesale & retail | 2016 |
| John Ellis Builders Limited | Construction | 1988 |
| John Fitzpatrick Ltd | Mining & quarrying | 2009 |
| John Gibson Interiors Ltd | Construction | 2025 |
| John Goodrick Equestrian Developments Limited | Manufacturing | 2004 |
| John Green Designs Ltd | Manufacturing | 2023 |