| J Latham Electrical Services Ltd | Construction | 2023 |
| J Litten Properties Limited | Real estate | 2023 |
| J LUX Lounge Ltd | Other services | 2025 |
| J M Property Hull Ltd | Real estate | 2025 |
| J Marr (Management) Services Limited | Extraterritorial | 2008 |
| J Marshall ALT Limited | Financial services | 2011 |
| J Mckee Joinery Holdings Limited | Financial services | 2018 |
| J Mckee Joinery Ltd | Construction | 2008 |
| J Miller Electrical Ltd | Construction | 2012 |
| J P Carter Transport Ltd | Transport & logistics | 2021 |
| J Pockley Limited | Wholesale & retail | 1955 |
| J R Driveways and Drop Kerbs Ltd | Construction | 2017 |
| J R Rice Engineering Limited | Construction | 2014 |
| J Ribbons Funeral Services Limited | Other services | 2017 |
| J S Power Limited | Wholesale & retail | 2004 |
| J S Subsea Services Ltd | Manufacturing | 2017 |
| J Soanes Limited | Construction | 2018 |
| J Software Engineer Limited | Information & communication | 2026 |
| J Temp Wind Services Limited | Administrative & support | 2024 |
| J V Private Ltd | Hospitality | 2025 |
| J Webster Properties Ltd | Real estate | 2024 |
| J Williams Tuition Limited | Education | 2023 |
| J Y (Hull) Limited | Real estate | 2025 |
| J&B General Operative Services Ltd | Professional & scientific | 2026 |
| J&K Commercials Limited | Manufacturing | 2015 |
| J&M Properties Hull Limited | Real estate | 2025 |
| J&M Property (Yorkshire) Ltd | Real estate | 2018 |
| J&M Waste Removal Ltd | Water & waste | 2025 |
| J&R Worthington Properties Limited | Construction | 2023 |
| J&S Plumbing and Heating Construction Ltd | Construction | 2024 |
| J&W Management Services Ltd | Hospitality | 2021 |
| J-Hut Investments Ltd | Real estate | 2019 |
| J. & H. Mclaren Ltd | Professional & scientific | 2021 |
| J. P. Cooke Limited | Health & social care | 2014 |
| J. W. O'Pray & Sons Limited | Manufacturing | 1976 |
| J.A Braithwaite Ltd | Agriculture & fishing | 2026 |
| J.C. Services and SON Limited | Construction | 2000 |
| J.D. Building Contractors Limited | Construction | 1992 |
| J.J.N. Mackman Limited | | 1936 |
| J.K.T. Property Management Ltd | Real estate | 2002 |
| J.M. Diamond Limited | Manufacturing | 2022 |
| J.Olsson Services Ltd | Construction | 2022 |
| J.P. Barkworth Limited | Wholesale & retail | 2003 |
| J.P. Developers Limited | Construction | 1999 |
| J.P.C Travel Ltd | Transport & logistics | 2018 |
| J.R. RIX & Sons Limited | Wholesale & retail | 1957 |
| J.R.H Fire & Security Services Limited | Administrative & support | 2017 |
| J14 Cars Ltd | Wholesale & retail | 2020 |
| J14 Wheels Ltd | Wholesale & retail | 2022 |
| J5 Digital Ltd | Information & communication | 2026 |
| J88SON Property Limited | Real estate | 2024 |
| JA Batac Ltd | Health & social care | 2026 |
| JA Fitting Services Limited | Construction | 2016 |
| JAB Clothing Limited | Wholesale & retail | 2025 |
| JAC Mart Limited | Wholesale & retail | 2025 |
| JAC Properties (Hull) Limited | Real estate | 2016 |
| Jacek Duniec Transport Ltd | Transport & logistics | 2015 |
| Jack Chamberlain Creative Ltd | Arts & recreation | 2023 |
| Jack Harman Plumbing & Heating Limited | Construction | 2018 |
| Jack Harvey Smith Dance Company CIC | Education | 2025 |
| Jack Mankel Media Limited | Professional & scientific | 2023 |
| Jack OV ALL Ltd | Construction | 2025 |
| Jack's Glass Ltd | Manufacturing | 2018 |
| Jacket Spa Limited | Extraterritorial | 2008 |
| Jackrumneyltd Ltd | Construction | 2026 |
| Jackson Dental Supplies Limited | Health & social care | 1994 |
| Jackson GAS & Heating Ltd | Construction | 2026 |
| Jackson Renewable Ltd | Manufacturing | 2024 |
| Jackson Systems Limited | Information & communication | 2019 |
| Jacobs Building and Civils Ltd | Construction | 2018 |
| JAD Beauty Ltd | Other services | 2014 |
| Jadan Press Limited | Administrative & support | 2008 |
| Jadco Hull LLP | | 2016 |
| Jaff Barber 1 Ltd | Other services | 2024 |
| JAG Co 001 Limited | Professional & scientific | 2014 |
| Jagco (CCH) Limited | Administrative & support | 2016 |
| JAI Mahakal Ltd | Health & social care | 2023 |
| JAI Saiji Ltd | Health & social care | 2024 |
| Jake Everitt Hair Limited | Other services | 2025 |
| Jake Fieldhouse Consulting Ltd | Information & communication | 2025 |
| Jakewoods Capital Ltd | Financial services | 2025 |
| JAL Motors Ltd | Wholesale & retail | 2025 |
| Jalland Building Services Limited | Construction | 2009 |
| James a Kelly Instruments Ltd | Professional & scientific | 2024 |
| James Alexandre Limited | Manufacturing | 2020 |
| James Blake Wealth Management Limited | Professional & scientific | 2020 |
| James E. Smith (Northern) Limited | Manufacturing | 2009 |
| James Joseph Building Services Limited | Construction | 2018 |
| James Ledger Properties Limited | Construction | 2014 |
| James Legal Limited | Professional & scientific | 2009 |
| Jamie Shepherd Holdings Limited | Financial services | 2019 |
| Jamiehudson.Com Limited | Information & communication | 2003 |
| Jamma Investments Ltd | Professional & scientific | 2019 |
| Janda Property Development & Management Ltd | Real estate | 2021 |
| Janjor Cars Ltd | Construction | 2025 |
| Jank Limited | Real estate | 2001 |
| Janmel Ltd | Hospitality | 2018 |
| Japb Engineering Limited | Professional & scientific | 2022 |
| Japtech Hull Limited | Manufacturing | 2007 |
| JAR Property Group Ltd | Real estate | 2025 |