| Intra House Developments Limited | Real estate | 2000 |
| Intratec Limited | Real estate | 2015 |
| Intratune Limited | Information & communication | 2024 |
| Intriangle Solutions Limited | Wholesale & retail | 2008 |
| Inttax Limited | Professional & scientific | 2012 |
| Intuledge Limited | Education | 2025 |
| Inuus Limited | Information & communication | 2014 |
| Invenio Consulting Ltd | Administrative & support | 2013 |
| Inventia Healthcare (UK) Limited | Wholesale & retail | 2021 |
| Inventive Lends Limited | Financial services | 2017 |
| Inventix Limited | Wholesale & retail | 2025 |
| Inventories and Property Services Limited | Other services | 2012 |
| Inventory Link Ltd | Real estate | 2011 |
| Inverness Estates Limited | Real estate | 2021 |
| Invero Limited | Wholesale & retail | 2009 |
| Invest Mondial Limited | Real estate | 2018 |
| Invest Property Management Limited | Real estate | 2007 |
| Investar Holdings Limited | Real estate | 2025 |
| Investing Champions Ltd | Wholesale & retail | 2023 |
| Investment Homes Limited | Real estate | 2006 |
| Investments & Loans Limited | Financial services | 2009 |
| Investwell Management Ltd | Real estate | 2016 |
| Invicta Capital Limited | Administrative & support | 2001 |
| Invicta Custodial Limited | Extraterritorial | 2013 |
| Invicta Investments Plus Ltd | Real estate | 2017 |
| Invictus Professionals Ltd | Information & communication | 2014 |
| Invictus R&D Ltd | Manufacturing | 2016 |
| Involved Design Ltd. | Professional & scientific | 2015 |
| Involved Property Ltd | Real estate | 2021 |
| Inzai Ltd | Real estate | 2024 |
| IOM Drylining Ltd | Construction | 2015 |
| Iomiro Ltd | Transport & logistics | 2024 |
| ION Accountants Limited | Professional & scientific | 2019 |
| ION Films Limited | Information & communication | 1998 |
| ION Gardens Ltd | Administrative & support | 2016 |
| ION Information Technologies Limited | Information & communication | 1995 |
| Ionel Ispas Ltd | Construction | 2021 |
| Ionesi Group Ltd | Construction | 2018 |
| Ionul Pozitiv Ltd | Wholesale & retail | 2024 |
| Ionut Hopulele Limited | Transport & logistics | 2019 |
| IOO Dental Limited | Health & social care | 2020 |
| Ioptimise IT Consultancy Services Ltd | Information & communication | 2024 |
| Iordachi Ltd | Wholesale & retail | 2025 |
| Iorek Cloud Technologies Limited | Information & communication | 2017 |
| IP Patel Limited | Other services | 2026 |
| IPA Tech Limited | Professional & scientific | 2015 |
| IPC Builders and Developers UK Ltd | Construction | 2024 |
| IPE Capital Limited | Real estate | 2011 |
| Ipech Limited | Wholesale & retail | 1998 |
| Ippu Group Ltd | Financial services | 2020 |
| Ipublisher Ltd | Information & communication | 2021 |
| Iqbal Knitting Ltd | Wholesale & retail | 2024 |
| IR Property & Maintenance Ltd | Professional & scientific | 2025 |
| IRA Process Solutions Ltd | Professional & scientific | 2012 |
| IRA Technologies Ltd | Information & communication | 2018 |
| Iracons Ltd | Professional & scientific | 2026 |
| Iraya Digital Ltd | Wholesale & retail | 2026 |
| Iraye Group Limited | Other services | 2020 |
| Irayemf Ltd | Professional & scientific | 2026 |
| IRECRUIT24 Limited | Administrative & support | 2017 |
| Irem Holdings Ltd | Financial services | 2026 |
| Irene Homes Ltd | Real estate | 2023 |
| Ireni Limited | Administrative & support | 2020 |
| Irestergroup Ltd | Construction | 2018 |
| IRH Services Ltd | Information & communication | 2025 |
| Iris Concepts Limited | Administrative & support | 2015 |
| Iris Medical Communication Limited | Health & social care | 2025 |
| Iris Real Estates Ltd | Real estate | 2011 |
| Irml Ltd | Wholesale & retail | 2025 |
| Irmora Prime Ltd | Wholesale & retail | 2026 |
| Irock Limited | Real estate | 2021 |
| Ironmen Tech Ltd | Construction | 2014 |
| Irvine Estates Ltd | Real estate | 2025 |
| Irwin Plastering Ltd | Construction | 2022 |
| Irya Infotech Ltd | Information & communication | 2019 |
| Irzo Limited | Professional & scientific | 2018 |
| IS Accounting Services Ltd | Professional & scientific | 2013 |
| IS Bailiff Services Limited | Administrative & support | 2025 |
| ISA Commercial Refrigeration (UK) Limited | Manufacturing | 1999 |
| Isaac Collins Bespoke Limited | Manufacturing | 2023 |
| Isabelle Van Keulen Ltd | Arts & recreation | 2019 |
| Isache Building Ltd | Construction | 2019 |
| Isaro Capital Limited | Real estate | 2024 |
| Isaro Investments Limited | Real estate | 2026 |
| ISD Homes Limited | Construction | 2015 |
| ISE Investments Limited | Real estate | 2014 |
| ISG Chauffeur and Hire Limited | Transport & logistics | 2025 |
| ISG Enterprise Limited | Other services | 2020 |
| ISH Healthcare Ltd | Wholesale & retail | 2021 |
| Isha International Ltd | Professional & scientific | 2023 |
| Isha Nivaas Ltd | Real estate | 2026 |
| Ishana Properties Limited | Real estate | 2010 |
| Ishlo Ltd | Wholesale & retail | 2024 |
| Ishtar Bakery Ltd | Wholesale & retail | 2025 |
| Ishtar Grill Ltd Limited | Hospitality | 2024 |
| Ishtar Restaurant Limited | Hospitality | 2025 |
| Ishvary Limited | Wholesale & retail | 2025 |
| Ishwa Smile Ltd | Other services | 2019 |
| Ishwar Properties Ltd | Real estate | 2024 |
| ISI92 Limited | Public administration | 2021 |