| IOW Home Solutions Ltd | Construction | 2021 |
| IOW OR Nowhere Ltd | Wholesale & retail | 2025 |
| IOW Panthers Ltd | Arts & recreation | 2026 |
| IOW Residential Limited | Real estate | 2008 |
| IP Consultancy Limited | Construction | 2025 |
| IP Converged Solutions Ltd | Information & communication | 2021 |
| IP Holdco Limited | Financial services | 2026 |
| IP Projects Ltd | Construction | 2020 |
| IP Reporting Ltd | Health & social care | 2016 |
| IPARTS4U Limited | Wholesale & retail | 2013 |
| IPB Engineering Services Ltd | Manufacturing | 2015 |
| Iprogram Ltd. | Information & communication | 2020 |
| Iprotein Limited | Manufacturing | 2018 |
| IQA+ Ltd | Information & communication | 2011 |
| Iqbal Autos Ltd | Wholesale & retail | 2026 |
| Iqbal Law Associates (UK) Ltd | Professional & scientific | 2023 |
| Iqra & Inaaya & Zakariya Ltd | Transport & logistics | 2021 |
| Irenesbabyboutique Ltd | Wholesale & retail | 2025 |
| Irex Grace Limited | Information & communication | 2023 |
| Irmaa (NPT) Limited | Professional & scientific | 2019 |
| Irmaa Properties Ltd | Construction | 2018 |
| Irmak Project Management Ltd | Professional & scientific | 2026 |
| IRN Property Ltd | Real estate | 2023 |
| Iron FAB Engineering Limited | Professional & scientific | 2020 |
| Ironworks UK by Marcos Antonio Limited | Manufacturing | 2019 |
| IS Management Ltd | Professional & scientific | 2021 |
| IS Sales Ltd | Wholesale & retail | 2025 |
| Isablog Ltd | Information & communication | 2023 |
| Isca Cleaners Limited | Administrative & support | 2014 |
| Isca Contracting Ltd | Professional & scientific | 2018 |
| Isca Cost Consultancy Services Ltd | Professional & scientific | 2025 |
| Isca Electrical Services Limited | Construction | 2023 |
| Isca Mortgage Solutions Limited | Financial services | 2019 |
| Isca Project Management Services Limited | Administrative & support | 2009 |
| Isca Property Group Ltd | Construction | 2021 |
| Isca Renewables Ltd | Construction | 2021 |
| Isca Solutions Ltd | Wholesale & retail | 2010 |
| Isca Wealth Management Limited | Financial services | 2019 |
| ISG Tamil Ltd | Education | 2022 |
| Island Aeronautical Ltd | Manufacturing | 2022 |
| Island Air Conditioning Limited | Energy | 2006 |
| Island Alarm Systems Ltd | Professional & scientific | 2008 |
| Island Automotive Ltd | Wholesale & retail | 2015 |
| Island Book-Keeping Bureau Limited | Financial services | 1995 |
| Island Ceilings and Developments Ltd | Construction | 2018 |
| Island Commercial Property Limited | Construction | 2014 |
| Island Community Ventures Limited | Wholesale & retail | 2010 |
| Island Crane Hire (IOW) Limited | Professional & scientific | 2007 |
| Island Crane Hire Limited | Construction | 1993 |
| Island Dermatology Ltd | Health & social care | 2024 |
| Island Facility Services Ltd | Construction | 2014 |
| Island Food Services (IOW) Limited | Wholesale & retail | 2010 |
| Island Ground Screws Ltd | Construction | 2023 |
| Island Harbour Residents Association 2011 Limited | Real estate | 2011 |
| Island Holiday Media Ltd | Information & communication | 2006 |
| Island Imperial Roofing Ltd | Construction | 2017 |
| Island Metalworks Ltd | Manufacturing | 2022 |
| Island Paving Ltd | Manufacturing | 2023 |
| Island PC Services Limited | Information & communication | 2008 |
| Island Pilates Centre Limited | Other services | 2007 |
| Island Property Holdings Limited | Construction | 2018 |
| Island Property Portfolios Ltd | Real estate | 2024 |
| Island Publications Ltd | Information & communication | 2025 |
| Island Renewables Ltd | Construction | 2019 |
| Island Riding Centre Arena Ltd | Arts & recreation | 2017 |
| Island Riding Centre Limited | Real estate | 2015 |
| Island Riding Centre Livery Ltd | Arts & recreation | 2017 |
| Island Rise Ltd | Wholesale & retail | 2025 |
| Island Sheetmetal Limited | Manufacturing | 2002 |
| Island Structural Limited | Manufacturing | 1996 |
| Island Support Services CIC | Health & social care | 2010 |
| Island Treatment Specialists Limited | Construction | 1984 |
| Island Youthways Ltd | Hospitality | 2021 |
| Islandcraft Designs Limited | Other services | 2006 |
| Islandwide Chimney Sweep Services Limited | Administrative & support | 2014 |
| Isle Build IT Ltd | Construction | 2026 |
| Isle Build Limited | Construction | 2022 |
| Isle Hold IT Ltd | Financial services | 2026 |
| Isle Love Sweets Ltd | Wholesale & retail | 2022 |
| Isle of Skye Media Ltd | Professional & scientific | 2025 |
| Isle of Wight Bars Ltd | Hospitality | 2021 |
| Isle of Wight Brewery Limited | Wholesale & retail | 2009 |
| Isle of Wight Care Partnership Community Interest Company | Other services | 2018 |
| Isle of Wight Citizens Advice Bureau | Information & communication | 1995 |
| Isle of Wight County Club Limited | Hospitality | 1900 |
| Isle of Wight County Show Limited | Arts & recreation | 1995 |
| Isle of Wight Cricket Board Limited | Arts & recreation | 2008 |
| Isle of Wight Distribution Limited | Transport & logistics | 2001 |
| Isle of Wight Environmental Ltd | Extraterritorial | 2021 |
| Isle of Wight Flood Response Team Limited | Administrative & support | 2023 |
| Isle of Wight Hunt Limited | Other services | 2008 |
| Isle of Wight Kitchens & Bedrooms Ltd. | Manufacturing | 2013 |
| Isle of Wight Motorcycle Club Limited | Arts & recreation | 2006 |
| Isle of Wight Mountain Bike Centre Community Interest Company | Arts & recreation | 2019 |
| Isle of Wight Property Ltd | Real estate | 2008 |
| Isle of Wight Scaffolding Ltd | Construction | 2024 |
| Isle of Wight Shepherd Huts Limited | Manufacturing | 2019 |
| Isle of Wight Society for the Blind | Health & social care | 2007 |
| Isle of Wight Specsavers Limited | Wholesale & retail | 1989 |
| Isle of Wight Speed Trials Ltd | Other services | 2022 |