| IAN Greaves Property Services Ltd | Administrative & support | 2026 |
| Ice 21 Ltd | Real estate | 2019 |
| Ignite Supplements Ltd | Wholesale & retail | 2023 |
| Ilical Limited | Information & communication | 2011 |
| Imci Investment Services Ltd | Professional & scientific | 2017 |
| Independent CDM Ltd | Professional & scientific | 2024 |
| Indo Aquatic Ltd | Wholesale & retail | 2026 |
| Indulge (Brough) Limited | Real estate | 2016 |
| Industar Limited | Wholesale & retail | 2014 |
| Industrial Motors & Controls Limited | Manufacturing | 2013 |
| Inhoco 3166 Limited | Professional & scientific | 2004 |
| Inhoco 3500 Limited | Financial services | 2026 |
| Innovative Graphics (Northern) Limited | Arts & recreation | 1982 |
| Insight Property Solutions Limited | Real estate | 2025 |
| Inspire Photos Ltd | Professional & scientific | 2022 |
| INT Hub Ltd | Health & social care | 2023 |
| Internet Demon Limited | Professional & scientific | 2011 |
| Intrepid Brewing Company Limited | Manufacturing | 2014 |
| Iport (UK) Limited | Wholesale & retail | 2010 |
| Isberg Holdings Ltd | Extraterritorial | 2018 |
| Isberg Limited | Administrative & support | 1985 |
| Isbrand Fish Sales Limited | Extraterritorial | 1989 |
| Isdance Group Ltd | Arts & recreation | 2026 |
| It's Everyone's Fight Limited | Real estate | 2019 |
| Ivanos Concepts Limited | Health & social care | 2026 |
| J & J South Cave Auto Repair Centre Ltd | Wholesale & retail | 2024 |
| J & L Plummer Eyecare Services Ltd | Health & social care | 2024 |
| J B Books Ltd | Wholesale & retail | 2020 |
| J B Electrical Contractors (Everthorpe) Ltd | Construction | 2026 |
| J D Cooling Service Limited | Construction | 2023 |
| J M Barrett Project Management Ltd | Professional & scientific | 2017 |
| J. H. Patchett & Sons Limited | Agriculture & fishing | 1952 |
| J. N. J. Malone Limited | Professional & scientific | 2006 |
| J. W. Beaumont Limited | Agriculture & fishing | 2021 |
| J.P. Transport (Yorkshire) Ltd. | Transport & logistics | 2003 |
| Jaifroid Ltd | Professional & scientific | 2019 |
| James a Comrie Limited | Administrative & support | 2018 |
| James a Lilacs Limited | Construction | 2025 |
| James Chapman Ltd | Financial services | 2023 |
| James Construction Services Limited | Construction | 2022 |
| James Developments Group Ltd | Construction | 2018 |
| James Structural Services Ltd | Construction | 2026 |
| Janvin Medical Ltd | Education | 2022 |
| Jarratt Hills Kennels and Cattery Limited | Other services | 2023 |
| Jate Property Ltd | Real estate | 2025 |
| Jawaid and Junaid Services Limited | Health & social care | 2023 |
| JB Online Stores Ltd | Wholesale & retail | 2023 |
| JDH Investments Limited | Information & communication | 1998 |
| Jeepey Limited | Wholesale & retail | 2010 |
| Jenkins Humber Limited | Transport & logistics | 2019 |
| Jesmond Engineering Limited | Professional & scientific | 2004 |
| Jesmond Engineering Trustees Limited | Administrative & support | 2025 |
| JET Park Storage Ltd | Transport & logistics | 2024 |
| Jetpark Developments Limited | Professional & scientific | 2002 |
| JF Consultancy Limited | Information & communication | 2020 |
| JH Software Services Ltd | Information & communication | 2020 |
| JJB Motors 25 Ltd | Wholesale & retail | 2022 |
| JK Healthcare (Brigg) Limited | Health & social care | 2022 |
| JMB Electrical Services Limited | Construction | 2003 |
| JML Estates Limited | Real estate | 2000 |
| JML Investments Limited | Real estate | 2002 |
| JML Properties Limited | Real estate | 1999 |
| JMS Global Wealth (UK) Ltd | Professional & scientific | 2020 |
| JNJ Cleaning Ltd | Administrative & support | 2020 |
| Johnson Consultancy Services Global Limited | Administrative & support | 2015 |
| Johnson Home Lettings Limited | Real estate | 2018 |
| Jonathan Forman Architects Limited | Professional & scientific | 2012 |
| Jones Funeral Directors (South Cave) Ltd | Other services | 2020 |
| JT Sparkle Homes Ltd | Real estate | 2026 |
| JVR Commercials Ltd | Wholesale & retail | 2019 |
| JW Properties (Yorkshire) Limited | Households | 2017 |
| Jyne Properties Limited | Households | 2025 |
| K&G Lettings Limited | Real estate | 2006 |
| K9 Fire Investigation. CIC | Other services | 2014 |
| Kabra Holdings Limited | Health & social care | 2019 |
| Kaesthetics by Kelsey Jade Ltd | Other services | 2026 |
| KAT Europe Limited | Manufacturing | 2011 |
| Kate Hainsworth Consulting Ltd | Professional & scientific | 2024 |
| KDL Yorkshire Limited | Professional & scientific | 2026 |
| Kenmed Limited | Health & social care | 2012 |
| Kent Building Developments Limited | Administrative & support | 2002 |
| KHR Contracting Ltd | Professional & scientific | 2015 |
| Killingwold Properties Ltd | Real estate | 2025 |
| Kingston Maintenance Ltd | Construction | 2025 |
| Kingston Properties (Yorkshire) Ltd | Real estate | 2017 |
| Kingston Upon Hull Swimming Club | Arts & recreation | 1998 |
| Kitchen & Bathroom Specialists Ltd | Construction | 2022 |
| Klick Refrigeration Limited | Extraterritorial | 2019 |
| KLW Care Ltd | Health & social care | 2021 |
| Knight Dornan Limited | Construction | 2020 |
| KP Property Ltd | Construction | 2026 |
| KPG Media Ltd | Information & communication | 2022 |
| KR Child's Place Ltd | Real estate | 2022 |
| Kraanen Properties Limited | Real estate | 2003 |
| Kreative Accounting Limited | Professional & scientific | 2020 |
| Kuriuus Software Ltd | Information & communication | 2026 |
| L Carr Contractors Ltd | Construction | 2021 |
| L2S Systems Ltd | Other services | 2013 |
| LA Salon Limited | Other services | 2019 |
| Lacada Ltd | Extraterritorial | 2020 |