| JOL Carparts Limited | Wholesale & retail | 2017 |
| Jola Joinery Limited | Construction | 2024 |
| Jolly B Makeovers Ltd | Wholesale & retail | 2026 |
| Jollyvent Limited | Administrative & support | 2004 |
| Jonathan Carter Limited | Professional & scientific | 2008 |
| Jonathan Forman Limited | Professional & scientific | 2011 |
| Jonathan FRY Automotive Ltd | Wholesale & retail | 2009 |
| Jonathan Smith Architects Limited | Professional & scientific | 2012 |
| Jones Funeral Directors Limited | Other services | 2016 |
| Jones UK Group Ltd | Construction | 2016 |
| Jonne Health Limited | Health & social care | 2023 |
| Jonza Limited | Wholesale & retail | 2021 |
| Jopling Electrical Contractors Limited | Construction | 2012 |
| Jordan Brough South Developments LLP | | 2016 |
| Jordans Motors Limited | Wholesale & retail | 2011 |
| Jordans Sunblinds Limited | Manufacturing | 1985 |
| Jordeine Aesthetics and Beauty Ltd | Other services | 2023 |
| Joroko Maintenance Ltd | Construction | 2025 |
| Jorvik Living Ltd | Construction | 2016 |
| Jose Escalera Ltd | Professional & scientific | 2017 |
| Josh Beet Fitness Limited | Education | 2017 |
| Jovisa Limited | Public administration | 2019 |
| Jovrex Group Limited | Administrative & support | 2026 |
| Joy Gledhill Limited | Manufacturing | 2001 |
| Joy Jungle Ltd | Education | 2025 |
| JP Counselling Ltd | Other services | 2023 |
| JP NDT Limited | Manufacturing | 2014 |
| JP Pipe Services Ltd | Construction | 2023 |
| JP Proton Limited | Professional & scientific | 2002 |
| JP Sandwich Ltd | Hospitality | 2025 |
| JP Spares and Solutions Ltd | Wholesale & retail | 2025 |
| JP Steel Services Ltd | Construction | 2024 |
| JPC Solutions Limited | Professional & scientific | 2012 |
| JPC Technical Design Ltd | Professional & scientific | 2012 |
| Jpim Work's Ltd | Wholesale & retail | 2021 |
| JR Engineering Services (UK) Limited | Professional & scientific | 2011 |
| JR Living Ltd | Real estate | 2022 |
| JRF Heating Limited | Construction | 2024 |
| Jrjs Holdings Ltd | Real estate | 2023 |
| JRL Homes Limited | Real estate | 2015 |
| JRL Land Limited | Real estate | 2015 |
| JRP Property Holdings Limited | Real estate | 2016 |
| JRR Capital Limited | Wholesale & retail | 2018 |
| JRS (P&H) Limited | Construction | 2010 |
| JRS Properties & Lettings Limited | Real estate | 2017 |
| JS Air Tech Ltd | Energy | 2025 |
| JS Directions Limited | Professional & scientific | 2018 |
| JS Home Services Ltd | Construction | 2024 |
| JSA Property Limited | Real estate | 2018 |
| JSC Business Consultants Ltd | Professional & scientific | 2026 |
| Jsdearnley Ltd | Wholesale & retail | 2025 |
| JSH Offshore Rigging Ltd | Professional & scientific | 2019 |
| JSK Properties Vinush and Rishan Ltd | Construction | 2021 |
| JSP Travel Services Ltd | Transport & logistics | 2024 |
| JSS Properties Ltd | Real estate | 2011 |
| JT Accountancy Services Limited | Professional & scientific | 2022 |
| JT Leisure Limited | Hospitality | 2025 |
| JT Portfolio Properties Ltd | Real estate | 2025 |
| JT Renewable Energy Services Ltd | Manufacturing | 2024 |
| Jtak Limited | Households | 2025 |
| JTS Group Limited | Manufacturing | 2025 |
| JTS Hull Limited | Transport & logistics | 2023 |
| Jubilee Central Ltd | Real estate | 2023 |
| Jubilee Church Hull | Other services | 2007 |
| Jugaluxe Ltd | Wholesale & retail | 2025 |
| Juicy Relationship Consults Ltd | Information & communication | 2025 |
| Juma Properties Limited | Real estate | 2013 |
| Juna Solutions Ltd | Health & social care | 2025 |
| Juniper Cakery Limited | Wholesale & retail | 2012 |
| Jupiter Document Management Solutions Limited | Administrative & support | 2024 |
| Jupiter Property Group Limited | Real estate | 2019 |
| Jusaso Ltd | Hospitality | 2023 |
| Just 11 Limited | Hospitality | 2023 |
| Just Automatics UK Ltd | Wholesale & retail | 2022 |
| Just Desserts & Coffee Ltd | Hospitality | 2013 |
| Just Electrolysis Ltd | Other services | 2021 |
| Just Emil Aesthetics Ltd | Other services | 2023 |
| Just Gilbey IT Solutions Ltd | Professional & scientific | 2015 |
| Just LVT Limited | Construction | 2026 |
| Just Mots Hull Ltd | Wholesale & retail | 2010 |
| Just Smart Bodyworks Limited | Wholesale & retail | 2020 |
| Just Spray IT Ltd | Construction | 2019 |
| Just Vitality Clinic Ltd | Health & social care | 2025 |
| Just-Valet Limited | Administrative & support | 2021 |
| Justice for ALL | Other services | 2023 |
| Jutt Online Marketing Limited | Wholesale & retail | 2025 |
| JVB Joinery Ltd | Construction | 2023 |
| JW Clearance Services Ltd | Transport & logistics | 2020 |
| JW Fitness Ltd | Other services | 2024 |
| JW Plumbing and GAS Services Limited | Construction | 2021 |
| JW Rope Access Services Limited | Construction | 2015 |
| JWB Property Holding Limited | Real estate | 2026 |
| JWL Joinery (Hull) Ltd | Construction | 2024 |
| Jwra Consulting Limited | Professional & scientific | 2024 |
| JWS Electrical Services Ltd | Construction | 2024 |
| JWS Wardrobes (Holdings) Limited | Financial services | 2022 |
| Jypm Ltd | Professional & scientific | 2012 |
| K & K Hull Limited | Hospitality | 2024 |
| K & K Projects Commercial Building & Scaffolding Ltd | Construction | 2023 |
| K & L Property Lettings Limited | Real estate | 2024 |