| IMS Concepts HX Limited | Professional & scientific | 2015 |
| IN Carpets & Flooring Ltd | Other services | 2018 |
| IN Sync FM Limited | Information & communication | 2017 |
| IN the CAN Limited | Information & communication | 2016 |
| In-Gage Technologies Limited | Information & communication | 2015 |
| In-Line Electrical Services (Holdings) Ltd | Construction | 2023 |
| In-Line Electrical Services Ltd | Construction | 2009 |
| In-Synergy Group Ltd | Professional & scientific | 2021 |
| In-Synergy Marketing SPV Ltd | Financial services | 2021 |
| Independent Health Care Solutions Limited | Financial services | 1995 |
| Independent Print Service Ltd | Professional & scientific | 2013 |
| Indesteel Limited | Professional & scientific | 2017 |
| Indigo Corporation Limited | Real estate | 2004 |
| Indigo Destination Management Ltd | Professional & scientific | 2017 |
| Inferspace Limited | Professional & scientific | 2020 |
| Infinite Edge Controlagies Ltd | Wholesale & retail | 2025 |
| Infinite Spark Solutions Ltd | Wholesale & retail | 2025 |
| Infinitegloorizon Group Ltd | Wholesale & retail | 2025 |
| Infinity ME Limited | Administrative & support | 2018 |
| Infinium Consulting Limited | Professional & scientific | 2013 |
| Infinium Holdings Limited | Financial services | 2016 |
| Infinium Property Limited | Real estate | 2013 |
| Influence Trading Solutions Limited | Wholesale & retail | 2024 |
| Inframe Bespoke Kitchens Limited | Manufacturing | 2020 |
| Ingfield Farm Shop Limited | Wholesale & retail | 2003 |
| Ingrave Bushey Ltd | Wholesale & retail | 2025 |
| Ingwood Parade 1966 Limited | Extraterritorial | 2014 |
| Inhaus Property Group Ltd | Real estate | 2026 |
| Inhouse Repair Team Ltd | Construction | 2023 |
| Injectors & Glow Plugs Removals Limited | Wholesale & retail | 2014 |
| INK Wala Ltd | Wholesale & retail | 2021 |
| Innate Repair Limited | Health & social care | 2019 |
| Inner Media Limited | Information & communication | 2003 |
| Inner Vision Productions Limited | Information & communication | 2016 |
| Innings Limited | Hospitality | 2004 |
| Innovation Health Care Recruitment Ltd | Other services | 2017 |
| Innovative Handling Solutions Limited | Extraterritorial | 2014 |
| Innovative Handling Systems Limited | Extraterritorial | 2014 |
| Innovatr Group Limited | Professional & scientific | 2020 |
| Inocon Limited | Construction | 2013 |
| Inomed Healthcare Limited | Wholesale & retail | 2020 |
| Insa Limited | Wholesale & retail | 2015 |
| Inside Outside Maintenance Services Ltd | Construction | 2023 |
| Inside the Masters Limited | Arts & recreation | 2015 |
| Inside-Out Branding Limited | Professional & scientific | 1997 |
| Inspiral Consulting Ltd | Professional & scientific | 2008 |
| Inspiring Steps CRC Ltd | Health & social care | 2025 |
| Inspirit Learning Partners Ltd | Other services | 2012 |
| Instacom Controls Ltd | Construction | 2020 |
| Instacom Holdings Ltd | Real estate | 2022 |
| INSTALL4ALL Limited | Construction | 2017 |
| Instapharma Ltd | Financial services | 2015 |
| Integral Signs & Graphics Limited | Professional & scientific | 2016 |
| Integrated Management Risk Services Ltd | Professional & scientific | 2015 |
| Intelligent Accounting Limited | Information & communication | 2005 |
| Intelligent Cooling Limited | Manufacturing | 2019 |
| Intelligent GMS Limited | Information & communication | 2026 |
| Intellisupport Limited | Information & communication | 2007 |
| Intermotors (Car Sales) Limited | Wholesale & retail | 2014 |
| Intermotors Limited | Wholesale & retail | 2012 |
| International Cashmere Fibres Limited | Extraterritorial | 2004 |
| International Centre for Coaching in Education Ltd | Education | 2020 |
| International Sourcing & Logistics Ltd | Wholesale & retail | 2024 |
| International Veterinary Orthopaedic Academy LLP | | 2007 |
| Intisarestatesandlettings Ltd | Real estate | 2025 |
| Intsolv Limited | Information & communication | 2015 |
| Intuitive Data Solutions Limited | Information & communication | 2002 |
| Intuitive PMO Limited | Professional & scientific | 2017 |
| Inventa Group Limited | Wholesale & retail | 2015 |
| Inventa Property Limited | Real estate | 2009 |
| Investbest Ltd | Real estate | 2016 |
| Investments for Good Ltd | Financial services | 2020 |
| Invictus Golf Studio Ltd | Arts & recreation | 2022 |
| Inyostore Ltd | Wholesale & retail | 2023 |
| IOF Limited | Health & social care | 2016 |
| IOG Developments Ltd | Real estate | 2018 |
| Ionexim Ltd | Other services | 2019 |
| Ionut Grad Logistics Ltd | Transport & logistics | 2020 |
| IP Electrical Services Ltd | Construction | 2021 |
| IPE Inspection Ltd | Professional & scientific | 2016 |
| IPE Property Maintenance Ltd | Construction | 2023 |
| Ipimp Clothing Ltd | Wholesale & retail | 2022 |
| Ipro Sales Limited | Professional & scientific | 2014 |
| Iram Ikram Ltd | Public administration | 2021 |
| Ironshield Resin and Groundworks Ltd | Construction | 2026 |
| Ironview Properties Ltd | Real estate | 2025 |
| Irving Anaesthetic Services Ltd | Health & social care | 2022 |
| Irving Consulting Ltd | Administrative & support | 2025 |
| IRY Group Ltd | Professional & scientific | 2022 |
| IRY Properties Ltd | Real estate | 2025 |
| Isaa Global (2) Ltd | Arts & recreation | 2023 |
| ISH Fabrications Limited | Manufacturing | 2014 |
| Isha Auto Repairs & Salvage Ltd | Wholesale & retail | 2023 |
| Ishf Ltd | Wholesale & retail | 2025 |
| Ishyy.Com Ltd | Wholesale & retail | 2025 |
| Islam Halifax CIC | Education | 2012 |
| Ismaeelr Ltd | Health & social care | 2024 |
| Ismay Wilburn Ltd | Wholesale & retail | 2025 |
| Isolde Ltd | Arts & recreation | 2018 |
| Isoptimiser Limited | Wholesale & retail | 2024 |