| HUX Public Relations Limited | Professional & scientific | 2023 |
| Hvac Communications Ltd | Manufacturing | 2011 |
| Hyde Developments UK Limited | Extraterritorial | 2003 |
| Hyde Engineering Solutions Ltd | Real estate | 2023 |
| Hyde Industrial Consultancy Ltd | Professional & scientific | 2024 |
| Hydration+ Ltd | Wholesale & retail | 2020 |
| Hydro Heat Plumbing and Heating Limited | Construction | 2025 |
| Hydroheat Plumbing&Gas Ltd | Construction | 2016 |
| Hydrov Holdings Ltd | Financial services | 2022 |
| Hydrov Investments Limited | Financial services | 2026 |
| Hydrov Ltd | Extraterritorial | 2022 |
| Hydrov Submersible Surveys Ltd | Professional & scientific | 2017 |
| Hydrov Tanks Ltd | Manufacturing | 2022 |
| Hydrov Testing Services Ltd | Professional & scientific | 2026 |
| Hydstar Ltd | Other services | 2024 |
| Hygiene Partners Limited | Hospitality | 2020 |
| Hygiene Reset Ltd | Administrative & support | 2026 |
| Hylton & Brown Ltd | Real estate | 2023 |
| Hylton & Co Property Ltd | Real estate | 2025 |
| Hylton Holdings Ltd | Financial services | 2025 |
| Hypercare Solutions Ltd | Manufacturing | 2025 |
| Hyperdown Services Ltd | Construction | 2018 |
| Hyperonex Ltd | Information & communication | 2025 |
| I D Bragger Limited | Professional & scientific | 2016 |
| I D I Commercial Cleaning Ltd | Administrative & support | 2018 |
| I DO Magazine Limited | Information & communication | 2011 |
| I E Bolt & NUT (2012) Limited | Manufacturing | 2012 |
| I H Sartorius Limited | Manufacturing | 2023 |
| I N Thompson Limited | Hospitality | 2023 |
| I&I Media Limited | Professional & scientific | 2025 |
| I-Investments Ltd | Administrative & support | 2014 |
| I-Source Vehicle Sourcing Specialist Ltd | Other services | 2024 |
| I.B.G. Auto Electrical Limited | Other services | 2004 |
| I4 Electrical Solutions Limited | Construction | 2025 |
| IAN Francis Consulting Ltd | Professional & scientific | 2017 |
| IAN Weatherston Limited | Professional & scientific | 2013 |
| Ian's Classic Carpets Limited | Wholesale & retail | 2011 |
| Ibathroom Solutions Ltd | Construction | 2012 |
| Ibbotson Holdings Limited | Financial services | 2022 |
| Ibex Robotics Limited | Other services | 2026 |
| IBN Holdings Limited | Financial services | 2016 |
| IBN Scaffold Access Limited | Construction | 2001 |
| Ibuild (UK) Ltd | Construction | 2001 |
| IC 101 Ltd | Professional & scientific | 2010 |
| Icare Autos Limited | Wholesale & retail | 2018 |
| Ice Kutty Fast Food Service Ltd | Hospitality | 2025 |
| Ice Ventilation Ltd | Construction | 2022 |
| Icon Pro Commercial Ltd | Construction | 2025 |
| Icon Pro Group Ltd | Construction | 2026 |
| Icon Pro-Renovations Ltd | Construction | 2024 |
| Iconic Edge Group Yorkshire Ltd | Construction | 2023 |
| Iconic Grimethorpe Limited | Construction | 2017 |
| Icool Equipment Ltd | Manufacturing | 2011 |
| ID Fit Outs Limited | Manufacturing | 2024 |
| ID Racking Consultancy Ltd | Manufacturing | 2023 |
| IDA Online Global Academy Ltd | Education | 2026 |
| IDA Portugal Ltd | Education | 2026 |
| Ideal Containers Ltd | Construction | 2019 |
| Iekos Ltd | Professional & scientific | 2019 |
| IFC15 Limited | Hospitality | 2026 |
| Iframe Windows and Doors Limited | Construction | 2021 |
| IG Service (Yorkshire) Limited | Construction | 2026 |
| IGC Memorials Limited | Manufacturing | 2017 |
| IGC Solid Surfaces Ltd | Manufacturing | 2012 |
| IGK Property Services Ltd | Construction | 2020 |
| Igloo Technology Group Ltd | Construction | 2017 |
| Ignis Safety Ltd | Professional & scientific | 2017 |
| Ignit Ltd | Wholesale & retail | 2024 |
| IJO Property Development Limited | Real estate | 2020 |
| IJR Holdings Limited | Real estate | 2020 |
| Ikconn Limited | Health & social care | 2016 |
| IKE Supported Housing Limited | Real estate | 2003 |
| Ilab Advisory Limited | Financial services | 2024 |
| Ileatrans Ltd | Transport & logistics | 2025 |
| Ilirian Vini Ltd | Hospitality | 2026 |
| ILJ Investments Ltd | Financial services | 2021 |
| ILM Castle Property Limited | Real estate | 2020 |
| IM Food Ltd | Hospitality | 2021 |
| Imagination Gaming Ltd | Extraterritorial | 2011 |
| Imagination Play Limited | Arts & recreation | 2025 |
| Imaktination Limited | Professional & scientific | 2016 |
| IMB Glow Ltd | Other services | 2024 |
| IMP UK Limited | Wholesale & retail | 2009 |
| Impact Framing Ltd | Wholesale & retail | 2006 |
| Impact Group Electrical Services Ltd | Construction | 2017 |
| Impact Powerwashing Limited | Construction | 2015 |
| Imperial Homes Yorkshire Limited | Construction | 2002 |
| Imperial Mews Ltd | Real estate | 2012 |
| IMS South Yorkshire Ltd | Wholesale & retail | 2004 |
| Imuk Solutions Ltd | Wholesale & retail | 2022 |
| IN House Yorkshire Limited | Professional & scientific | 2025 |
| In-Line Engineering Services (UK) Limited | Manufacturing | 2003 |
| Inclusion in Action C.I.C. | Education | 2014 |
| Inclusive Ping Pong Limited | Arts & recreation | 2012 |
| Incluziv Limited | Administrative & support | 2022 |
| Income for the Third AGE Ltd | Financial services | 2018 |
| Indeed Property Investments Ltd | Real estate | 2025 |
| Independent CAD Services Limited | Professional & scientific | 2008 |
| Independent Car Components Limited | Wholesale & retail | 2011 |
| Independent Financial Consultants Limited | Financial services | 2006 |