| Isle of Wight Hearing Centre Limited | Wholesale & retail | 2004 |
| Isle of Wight Indoor Bowls Club,Limited(The) | Arts & recreation | 1968 |
| Isle of Wight Interior Designs Ltd | Professional & scientific | 2017 |
| Isle of Wight Locums Ltd | Health & social care | 2010 |
| Isle of Wight Medical Services Ltd | Health & social care | 2018 |
| Isle of Wight Mushrooms Limited | Agriculture & fishing | 2019 |
| Isle of Wight Sports Achievement Awards Ltd | Arts & recreation | 2015 |
| Isle of Wight Tile Ltd | Construction | 2023 |
| Isle of Wight Windows Ltd | Construction | 2024 |
| Isle Paint and Maintain Limited | Construction | 2007 |
| Isle Shine Limited | Administrative & support | 2024 |
| Isle Wrap IT Limited | Hospitality | 2025 |
| Islebnb Holdings Ltd | Real estate | 2022 |
| Isoterm Ltd | Administrative & support | 2013 |
| Isovet Tanker Services Limited | Administrative & support | 2008 |
| Issie X Limited | Wholesale & retail | 2024 |
| IT (IOW) Limited | Wholesale & retail | 2023 |
| IT Gnosis Ltd | Information & communication | 2016 |
| IW Charter Ltd | Administrative & support | 2025 |
| IW Uniform Ltd | Wholesale & retail | 2018 |
| Iwso Productions Limited | Arts & recreation | 2018 |
| J & R Holland Limited | Construction | 2021 |
| J C Management (IW) Ltd | Households | 2013 |
| J M Projects (IOW) Limited | Construction | 2015 |
| J.A.M. Development (IW) Ltd | Construction | 2020 |
| J.P.R. Combustions Limited | Construction | 2002 |
| Jacks of Ryde Limited | Other services | 2014 |
| Jara Amusements Ltd | Arts & recreation | 2003 |
| Jazz Information Technology Limited | Information & communication | 1996 |
| JB Accessibility Ltd | Other services | 2025 |
| JBT Developments Limited | Construction | 2005 |
| JCH Aviation Ltd | Manufacturing | 2016 |
| JD Ventures (IOW) Limited | Construction | 2024 |
| Jeni Law (IW) Limited | Arts & recreation | 2017 |
| Jennychem Limited | Manufacturing | 2001 |
| JG Carpentry & Building IOW Ltd | Construction | 2026 |
| JGH Fabrications Limited | Manufacturing | 2015 |
| JH Productions Sales/Hire Ltd | Administrative & support | 2025 |
| JHN Healthcare Limited | Administrative & support | 2018 |
| JJ Aviation Ltd | Other services | 2018 |
| JJW Engineering Limited | Professional & scientific | 2026 |
| JKB Housing Ltd | Real estate | 2023 |
| JMD Building Consultancy Ltd | Professional & scientific | 2024 |
| JMH Publications Limited | Information & communication | 2005 |
| JML Consultancy Limited | Construction | 2010 |
| JMP Partnership (IW) Ltd | Construction | 2008 |
| JO Hummel Ltd | Arts & recreation | 2022 |
| Jodie Woodhouse Photography Ltd | Professional & scientific | 2025 |
| JOE Booth Repairs Ltd | Manufacturing | 2025 |
| John Buckman Design Limited | Professional & scientific | 2024 |
| John Cattle's Skate Club C.I.C. | Education | 2019 |
| Johnston Utilities Ltd | Construction | 2025 |
| Jolliffe Catering Ltd | Hospitality | 2025 |
| Jolly Homes Limited | Real estate | 2019 |
| Jones & Sons (IOW) Limited | Construction | 2014 |
| JRS Blade Repair Services Ltd | Manufacturing | 2026 |
| JRS Plumbing & Heating Limited | Construction | 2016 |
| JT Electrical Repairs Ltd | Other services | 2022 |
| Jyla Developments Ltd | Construction | 2021 |
| K & H Hair and Beauty Limited | Other services | 2023 |
| K & K Tutton Ltd | Administrative & support | 2020 |
| K & L Just Rentals Limited | Real estate | 2020 |
| K H Builders (IOW) Limited | Construction | 2012 |
| K K Properties Isle of Wight Limited | Real estate | 2021 |
| Kaiyo Group Ltd | Financial services | 2021 |
| Kaiyo Property Ltd | Real estate | 2021 |
| Kannama Ltd | Real estate | 2020 |
| Kannama Property Investments LLP | | 2022 |
| KB Graphics Limited | Information & communication | 2014 |
| KB Legal Consultants Ltd | Professional & scientific | 2025 |
| KDB Investments Limited | Real estate | 2024 |
| KEL Homes Limited | Real estate | 2024 |
| Kemphill Barn Holidays Limited | Hospitality | 2000 |
| Kenny’S Newport Ltd | Hospitality | 2023 |
| Kensington Place Residents Company Limited | Real estate | 2014 |
| KGM Investments Limited | Real estate | 2016 |
| Kgtec Ltd | Professional & scientific | 2019 |
| Kilgenny Limited | Real estate | 1970 |
| Kimberley House 30 George Street Ryde Limited | Real estate | 2007 |
| Kingswood Cooling Solutions Limited | Construction | 2012 |
| Kiss Accounting Ltd | Professional & scientific | 2021 |
| Kisscargo Limited | Transport & logistics | 2014 |
| Kitty Mews Management Company Limited | Administrative & support | 2011 |
| KLD Project Solutions Ltd | Manufacturing | 2025 |
| KMB 101 Properties Ltd | Real estate | 2025 |
| KNL Childcare Limited | Education | 2001 |
| Knoxhowell Architects Ltd | Professional & scientific | 2019 |
| KO Media (UK) Limited | Professional & scientific | 2011 |
| Kopernik Ltd | Wholesale & retail | 2016 |
| Kowalski Building Services Ltd | Construction | 2015 |
| Kpsw Consulting Limited | Professional & scientific | 2015 |
| KT1 Investments Ltd | Real estate | 2024 |
| Kulik Heating & GAS Services Ltd | Construction | 2023 |
| Kulupu Limited | Information & communication | 2022 |
| L J Teal Roofing Services Ltd | Construction | 2018 |
| L'Île Dans LE Vent Ltd | Extraterritorial | 2020 |
| L.A.A GRP Ltd | Manufacturing | 2022 |
| Laburnum House (Ryde) Management Company Limited | Other services | 1990 |
| Landscape House Ltd | Real estate | 2022 |
| Larklands Consultancy Services Limited | Financial services | 2022 |