| Intrahost Limited | Information & communication | 2006 |
| Intro FX Limited | Financial services | 2018 |
| Intuitai Ltd | Information & communication | 2025 |
| Intvity Limited | Information & communication | 2021 |
| Invene Limited | Financial services | 2025 |
| Investment & Financial Research Limited | Information & communication | 2005 |
| Investment Management Energy (UK) Limited | Wholesale & retail | 2012 |
| Investment Partner Business Ltd | Wholesale & retail | 2026 |
| Investutrade Ltd | Financial services | 2023 |
| Invictus Installations Ltd | Construction | 2024 |
| Invocation Healthcare Ltd | Health & social care | 2025 |
| Inward Flourish Ltd | Information & communication | 2025 |
| Ionut & Valentin Limited | Transport & logistics | 2020 |
| IP Polymers Ltd | Water & waste | 2016 |
| IPC Services (Yorkshire) Limited | Professional & scientific | 2012 |
| IPN Auto Mobile Ltd | Wholesale & retail | 2025 |
| IR Builders Ltd | Construction | 2025 |
| Iranian Community of Hull | Other services | 2015 |
| Iriciuc Trans Ltd | Transport & logistics | 2020 |
| Iris Soulframe CIC | Wholesale & retail | 2025 |
| Iron Cirrus Limited | Professional & scientific | 2016 |
| Iron Empire Fitness Club Limited | Arts & recreation | 2015 |
| Iron Group Limited | Hospitality | 2020 |
| Ironmoon Properties Ltd | Real estate | 2023 |
| Irresista-Bulls UK Limited | Agriculture & fishing | 2020 |
| Irvings Cable Jointing Limited | Manufacturing | 2024 |
| Irwin Aviation Limited | Professional & scientific | 2019 |
| Irwin Mechanical Services Ltd | Wholesale & retail | 2024 |
| IS Traders (Hull) Ltd | Wholesale & retail | 2019 |
| Isaabl Beauty Limited | Wholesale & retail | 2025 |
| Isaac Signature Limited | Wholesale & retail | 2025 |
| Isaac Yeboah Studio Ltd | Arts & recreation | 2025 |
| ISC Surveying Ltd | Information & communication | 2024 |
| ISG Boiler Holdings Limited | Professional & scientific | 2000 |
| Islam Foods Ltd. | Wholesale & retail | 2001 |
| Islese UK International Universete Ltd | Education | 2021 |
| ISM Pension Services Ltd | Education | 2011 |
| Ismail Orthopaedics Limited | Health & social care | 2019 |
| Isso Consultancy Ltd | Professional & scientific | 2025 |
| Istanbul Barber 2025 Limited | Other services | 2025 |
| Istanbul Barber Hull Limited | Other services | 2019 |
| Istanbul Brothers Ltd | Hospitality | 2026 |
| Istanbul Fast Food Ltd | Hospitality | 2025 |
| IT @ Spectrum Limited | Information & communication | 1985 |
| IT Prodigies Ltd | Water & waste | 2021 |
| It@Spectrum North East Limited | Manufacturing | 1999 |
| Italia Gourmet Ltd | Hospitality | 2025 |
| Italian Gourmet Pizza Ltd | Hospitality | 2025 |
| Itbusinessman Limited | Administrative & support | 2019 |
| Iteagles Ltd | Information & communication | 2026 |
| Itforward Limited | Information & communication | 2000 |
| ITH Vehicle Solutions Limited | Wholesale & retail | 2024 |
| Itlegendz Ltd | Information & communication | 2025 |
| Itlinx Limited | Administrative & support | 2005 |
| ITS Chloe Hill Media (UK) Ltd | Arts & recreation | 2024 |
| ITS Shelfco Ltd | Information & communication | 2007 |
| Itsi Business Limited | Information & communication | 2026 |
| Itsi Global Limited | Financial services | 2025 |
| Itsi Mobile Limited | Information & communication | 2024 |
| Itsi Technologies Limited | Information & communication | 2026 |
| Itsl Sound & Light Limited | Professional & scientific | 2014 |
| IV 2 Go Ltd | Health & social care | 2022 |
| Ivanhoe Leisure Group Limited | Professional & scientific | 1984 |
| Ivanhoe Property Group Ltd | Real estate | 2024 |
| Ivanov&Smales Pharm Ltd | Wholesale & retail | 2013 |
| Ivory Travel Limited | Administrative & support | 2024 |
| IVY Court Management Company Limited | Households | 2020 |
| Ivywus Consulting Legal Ltd | Professional & scientific | 2025 |
| Ivy’S Doll House Ltd | Other services | 2025 |
| Ixhull Limited | Extraterritorial | 2016 |
| Iyretail Ltd | Manufacturing | 2022 |
| Izedo Group Ltd | Administrative & support | 2025 |
| Izzy Entertainment Ltd | Arts & recreation | 2025 |
| Izzy Takeaway (2025) Limited | Hospitality | 2025 |
| J & a Smales Limited | Agriculture & fishing | 2015 |
| J & B International Consulting Ltd | Professional & scientific | 2011 |
| J & C Medical Limited | Health & social care | 2025 |
| J & C R Wood Limited | Manufacturing | 2011 |
| J & E Slots Unlimited | Arts & recreation | 2019 |
| J & K Leisure (Hull) Ltd | Manufacturing | 2025 |
| J & M Training Services Hull Limited | Education | 2015 |
| J & S Friary Ltd | Hospitality | 2025 |
| J Atkinson Roofing Ltd | Construction | 2024 |
| J Barlow Civils Ltd | Construction | 2023 |
| J Baxter and Sons Building Contractors Ltd | Construction | 2025 |
| J Bell Services Ltd | Construction | 2018 |
| J Burgess (Construction) Limited | Construction | 2014 |
| J C Leisure Connexions Limited | Wholesale & retail | 2003 |
| J C Leisure Connexions (EOT) Limited | Financial services | 2023 |
| J C Leisure Limited | Extraterritorial | 2009 |
| J Clark Technical Ltd | Manufacturing | 2018 |
| J D Childcare Ltd | Health & social care | 2002 |
| J D Quality Homes Limited | Construction | 2015 |
| J D Quality Lettings Limited | Real estate | 2016 |
| J H Aylett Property Limited | Real estate | 2022 |
| J Honaker Limited | Other services | 2018 |
| J J R Norrie Ltd | Manufacturing | 2018 |
| J J TYE Limited | Construction | 2025 |
| J Judd Renewables Limited | Professional & scientific | 2024 |
| J K Art Haven Ltd | Wholesale & retail | 2025 |