| Inshape Fitness (Isle of Wight) Ltd | Professional & scientific | 2020 |
| Inshape Fitness Studio Ltd | Arts & recreation | 2012 |
| Insignia Maritime Limited | Manufacturing | 2020 |
| Interactive Solutions Ltd | Administrative & support | 2020 |
| International Clinical Analytical and Scientific Services Ltd | Education | 2022 |
| Into the Blue Limited | Arts & recreation | 2003 |
| Invivid Limited | Information & communication | 2012 |
| Iona Acquisition Limited | Financial services | 2022 |
| IOW Laser Cleaning Services Limited | Administrative & support | 2026 |
| IOW Pilates Teacher Training Limited | Arts & recreation | 2025 |
| IOW Stocktakers Ltd | Professional & scientific | 2018 |
| IS IT Meant to DO That? Ltd | Information & communication | 2013 |
| Island Beach Netball CIC | Arts & recreation | 2025 |
| Island Care Limited | Health & social care | 1992 |
| Island Competitions Ltd | Arts & recreation | 2023 |
| Island Computer Systems Limited | Wholesale & retail | 1987 |
| Island Marine Dive Services Ltd | Manufacturing | 2026 |
| Island of Spice Limited | Hospitality | 2023 |
| Island Retrofit Ltd | Professional & scientific | 2022 |
| Island Ribs Developments Ltd | Professional & scientific | 2025 |
| Island Ribs Manufacturing Ltd | Manufacturing | 2025 |
| Island Sailing Club Ltd | Other services | 2020 |
| Island Sailing Club Property Ltd | Hospitality | 2021 |
| Island Shisha Ltd | Arts & recreation | 2025 |
| Isle of Wight Biosphere Ltd | Professional & scientific | 2024 |
| Isle of Wight Blinds Ltd | Construction | 2023 |
| Isle of Wight Community Rail Partnership CIC | Professional & scientific | 2024 |
| Isle of Wight Foodbank | Hospitality | 2011 |
| Isle of Wight Jobs Limited | Professional & scientific | 2013 |
| Isle of Wight Jobs Recruitment Limited | Professional & scientific | 2017 |
| Isle of Wight Jobs Training Ltd | Education | 2024 |
| Isle of Wight Open Studios CIC | Arts & recreation | 2024 |
| Isle of Wight Properties Ltd | Construction | 2003 |
| Islegame Ltd | Information & communication | 2025 |
| Isletalk CIC | Health & social care | 2016 |
| Isleview Properties Ltd | Real estate | 2023 |
| Isurf Limited | Arts & recreation | 2022 |
| Itchy Bear Ltd | Financial services | 2023 |
| IW Marine Ltd. | Financial services | 2023 |
| J P & S L Pedder | | 2005 |
| J. Samuel White & Company (Scotland) Limited | | 1954 |
| J.C Heating (IW) Limited | Construction | 2009 |
| Jack Thompson Consulting Ltd | Professional & scientific | 2022 |
| JAM & Sons Limited | Real estate | 2008 |
| Jasper's Coffee Limited | Manufacturing | 2021 |
| JB GAS Services IOW Ltd | Construction | 2020 |
| JBT Access Ltd | Professional & scientific | 2024 |
| JCH Marine Limited | Administrative & support | 2023 |
| JDG Administration & Compliance Ltd | Professional & scientific | 2026 |
| Jenor Limited | Wholesale & retail | 2002 |
| JEP GAS & Plumbing Limited | Construction | 2026 |
| Jiggle Pals Ltd | Manufacturing | 2025 |
| JJ Wind Solutions Limited | Professional & scientific | 2025 |
| JJM Design & Construction Ltd | Construction | 2015 |
| JKG Engineering Consultants Ltd | Professional & scientific | 2017 |
| JM & RJ Chandler Limited | Construction | 2011 |
| JM Bxng Ltd | Arts & recreation | 2025 |
| JO Bowden Marketing Limited | Professional & scientific | 2015 |
| Jocklish Limited | Wholesale & retail | 2021 |
| John Groves (IW) Limited | Construction | 1973 |
| Joints Cabinetry Ltd | Construction | 2020 |
| Jolliffe Cowes Ltd | Hospitality | 2023 |
| Jolliffes Cowes Limited | Hospitality | 2020 |
| JP Maritime Limited | Education | 2022 |
| JTG Advanced Composites Limited | Construction | 2024 |
| Jules Mantle Events Limited | Professional & scientific | 2005 |
| JWS Consulting Services Limited | Administrative & support | 2025 |
| K1 Retail Limited | Wholesale & retail | 2013 |
| Keenmedia Limited | Administrative & support | 2024 |
| Kendalls Fine Art Ltd | Wholesale & retail | 2013 |
| KGB Construction IW Limited | Construction | 2017 |
| Kgsailing Ltd | Arts & recreation | 2025 |
| Killearn Investments Limited | Administrative & support | 2010 |
| KIM Medical Ltd | Health & social care | 2022 |
| Kindmind Support Services Ltd | Public administration | 2025 |
| Kitova & John Ltd | Health & social care | 2019 |
| Knitit Gifts Ltd | Wholesale & retail | 2022 |
| KR Sustainability Ltd | Professional & scientific | 2020 |
| Kytrix Travel Limited | Transport & logistics | 2025 |
| L&T Bidco Limited | Financial services | 2026 |
| L.V. Ingrams & Company Limited | Financial services | 1998 |
| Lamor Corporation UK Limited | Administrative & support | 2003 |
| Lantern Living LLP | | 2025 |
| LBH Lettings Ltd | Real estate | 2022 |
| LCC 22 Limited | Households | 2022 |
| Leadercabs (IOW) Ltd | Transport & logistics | 2020 |
| Lease South Ltd | Financial services | 2024 |
| Leslies Isle of Wight Limited | Wholesale & retail | 2015 |
| Leslies Motors Limited | Wholesale & retail | 2016 |
| Letterbox Livefoods Ltd | Wholesale & retail | 2021 |
| Lexham Group Ltd | Wholesale & retail | 2025 |
| LH Blades Ltd | Manufacturing | 2025 |
| Library Street Capital Limited | Professional & scientific | 2018 |
| Lightwater Property Limited | Real estate | 2009 |
| Limewood Property Developments Limited | Construction | 2014 |
| Linton Exploration Limited | Information & communication | 1989 |
| Litfin Platform Limited | Financial services | 2020 |
| Litfinx Services Ltd | Professional & scientific | 2024 |
| Little Ladybirds Preschool Ltd | Education | 2018 |
| Little Locker Storage Ltd | Transport & logistics | 2025 |