| Hydrorider Limited | Extraterritorial | 2009 |
| Hydrorider UK Limited | Extraterritorial | 2009 |
| Hydrospin Limited | Extraterritorial | 2013 |
| Hydrotechnica Ltd | Professional & scientific | 2020 |
| Hygen Ltd | Construction | 2017 |
| Hygge Tean Ltd | Hospitality | 2022 |
| HYK Lodge Ltd | Health & social care | 2025 |
| Hylton Group Limited | Wholesale & retail | 1990 |
| Hype Cleaning Ltd | Administrative & support | 2023 |
| Hype Lettings Ltd | Real estate | 2021 |
| Hype Maintenance Ltd | Real estate | 2022 |
| Hypex Logistics Ltd | Transport & logistics | 2023 |
| I Delivery Management Limited | Professional & scientific | 2025 |
| I DO IT Services Ltd | Construction | 2026 |
| I E Energy Limited | Energy | 2019 |
| I E Energy Storage Limited | Energy | 2019 |
| I E Group Limited | Energy | 2019 |
| I E Renewables Limited | Energy | 2019 |
| I E Sustainability Limited | Energy | 2019 |
| I FIX Trains Limited | Transport & logistics | 2017 |
| I H Alasager Ltd | Hospitality | 2026 |
| I Oyslans Limited | Wholesale & retail | 2003 |
| I Roof 22 Ltd | Construction | 2022 |
| I&A Ventures Ltd | Wholesale & retail | 2026 |
| I&M Prime Stores Ltd | Wholesale & retail | 2026 |
| I&S Constructions Stoke Ltd | Construction | 2024 |
| I-Cosmetix Limited | Wholesale & retail | 2016 |
| I-Creation Impact Limited | Professional & scientific | 2025 |
| I-Tech 360 Ltd | Information & communication | 2023 |
| I. & P. Lifting Gear (Hire) Limited | Professional & scientific | 1982 |
| I.C Investments VTS Ltd | Financial services | 2023 |
| I.C.T. Electrical Limited | Construction | 2012 |
| I.H.Beauty Fashion Ltd | Wholesale & retail | 2019 |
| I.P.M. Building Contractors Limited | Construction | 2000 |
| I.Q Therapies Ltd | Other services | 2009 |
| I.T. Frost Limited | Administrative & support | 2010 |
| Iabtraders Limited | Wholesale & retail | 2025 |
| Iain Seath Golf Ltd | Administrative & support | 2023 |
| IAN C. Sandbach Limited | Real estate | 1958 |
| IAN Davies (Bramshall) Limited | Manufacturing | 2015 |
| IAN Evans Limited | Financial services | 2010 |
| IAN Johnson Developments Limited | Real estate | 2009 |
| IAN Knapper Limited | Manufacturing | 2008 |
| IAN Scott Retail Consulting Ltd | Professional & scientific | 2022 |
| Ianis&Filip Ltd | Transport & logistics | 2025 |
| IAP Cosmetics International Ltd | Manufacturing | 2018 |
| IAS Financial Consultants Ltd | Professional & scientific | 2025 |
| Ibecs Limited | Extraterritorial | 2009 |
| IBN Ahsan Limited | Other services | 2021 |
| Ibrahim Darwish Limited | Wholesale & retail | 2024 |
| Ibrahims Balti and Curry House Limited | Hospitality | 2019 |
| IC Mortgage Solutions Ltd | Financial services | 2023 |
| IC Publishing Ltd | Administrative & support | 2010 |
| ICA Mobile Tyres Ltd | Wholesale & retail | 2025 |
| Icanseal Ltd | Wholesale & retail | 2025 |
| Ice Chill Cryotherapy Limited | Health & social care | 2021 |
| ICG Builders Ltd | Construction | 2025 |
| Icmr Property & Investments Ltd | Real estate | 2025 |
| Iconex Ltd | Wholesale & retail | 2026 |
| Iconic Threadz Ltd | Wholesale & retail | 2025 |
| Icubicles Limited | Wholesale & retail | 2011 |
| ID Properties Limited | Real estate | 2016 |
| ID2 Holdings Limited | Financial services | 2014 |
| ID2 Media Limited | Information & communication | 2002 |
| Idea Pulse Limited | Real estate | 2025 |
| Ideal Estates Holding Ltd | Real estate | 2021 |
| Ideal Investment Properties Ltd | Real estate | 2019 |
| Ideal Kitchens and Bedrooms Limited | Manufacturing | 2006 |
| Identeq Ltd | Information & communication | 2019 |
| Idialyn Teal Limited | Wholesale & retail | 2023 |
| IDP Painting & Decorating Services Ltd | Construction | 2017 |
| Ieat Foods Limited | Administrative & support | 2022 |
| Iffyibeh Love & Relationship Hub Ltd | Professional & scientific | 2026 |
| IFK Legacy CIC | Arts & recreation | 2024 |
| Ifsobczwhy Ltd | Professional & scientific | 2018 |
| IG Infrastructure Solutions Ltd | Construction | 2024 |
| IGMA827 Ltd | Wholesale & retail | 2025 |
| Ignite Holdings (Staffs) Ltd | Financial services | 2025 |
| Ignite Nursing Ltd | Administrative & support | 2018 |
| IGV Studio Ltd | Professional & scientific | 2020 |
| IJ Structures Limited | Administrative & support | 2022 |
| IJA Engineering Ltd | Construction | 2026 |
| IJR Developments Ltd | Real estate | 2025 |
| IK Cars Limited | Wholesale & retail | 2019 |
| IK Unique Motorz Ltd | Wholesale & retail | 2021 |
| Iknowaytive Ltd | Information & communication | 2025 |
| Iknowwaytive Ltd | Information & communication | 2025 |
| ILA Training Ltd | Education | 2026 |
| Ileana Retails Ltd | Wholesale & retail | 2024 |
| ILK Ltd | Wholesale & retail | 2021 |
| Illam Homes Ltd | Real estate | 2026 |
| Illegal Nutrition Ltd | Manufacturing | 2018 |
| Illumination Holdings Limited | Financial services | 2017 |
| Ilybaba Retail Ltd | Wholesale & retail | 2025 |
| IM Health Consultant Ltd | Health & social care | 2023 |
| IM Installs Ltd | Construction | 2018 |
| IM PVT Ltd | Professional & scientific | 2024 |
| Imaan Investmentz Ltd | Real estate | 2025 |
| Imaan Real Estate Limited | Real estate | 2024 |
| Imadara Limited | Health & social care | 2024 |