| Innox Kitchens & Bathrooms Ltd | Construction | 2019 |
| Inola Guards Ltd | Administrative & support | 2025 |
| Inotexel Enterprise Ltd | Wholesale & retail | 2026 |
| Inplay Gaming Ltd | Arts & recreation | 2023 |
| Inpower Academy CIC | Education | 2016 |
| INS Properties Ltd | Real estate | 2019 |
| Insafe UK Limited | Administrative & support | 2019 |
| Insel Solutions Limited | Professional & scientific | 2014 |
| Inside Media Group Ltd | Information & communication | 2022 |
| Insideout Safehouse Limited | Wholesale & retail | 2023 |
| Insight Business Consulting Ltd | Administrative & support | 2025 |
| Insight Care Solutions Ltd | Other services | 2018 |
| Insight Care Training Ltd | Other services | 2018 |
| Insight Property Limited | Professional & scientific | 2005 |
| Insight Scan and Diagnostics Ltd | Health & social care | 2026 |
| Insight Training & Funerals Group Ltd | Education | 2024 |
| Insiya Luxe Limited | Wholesale & retail | 2025 |
| Insoft Services UK Ltd | Information & communication | 2015 |
| Inspace Systems Limited | Manufacturing | 2000 |
| Inspire Diversity Support CIC | Education | 2021 |
| Inspire Protection Solutions Holdings Limited | Construction | 2024 |
| Inspire Protection Solutions Limited | Construction | 2012 |
| Inspired Paths Haulage Limited | Transport & logistics | 2025 |
| Inspiredspaces Limited | Construction | 1983 |
| Inspiring Exceptional Performance Ltd | Construction | 2024 |
| Instal Expert Ltd | Construction | 2018 |
| Instaprint (Rugeley) Limited | Manufacturing | 2004 |
| Insterverlust Ltd | Professional & scientific | 2021 |
| Insulated Services (Wednesfield) Limited | Wholesale & retail | 1983 |
| Insulation, Design and Fabrications Limited | Construction | 2017 |
| Insulplast Limited | Construction | 2014 |
| Insurance 4U Services Limited | Financial services | 2018 |
| Inteerio PVT Ltd | Wholesale & retail | 2023 |
| INTEGR8 Finance Ltd | Professional & scientific | 2020 |
| Integra Supported Housing Limited | Administrative & support | 2013 |
| Integra Supported Housing Walsall Ltd | Health & social care | 2012 |
| Integral Concrete Solutions Limited | Construction | 2020 |
| Integral Manufacturing Limited | Manufacturing | 2020 |
| Integrated Children's Services Consultancy Limited | Education | 2005 |
| Integrated Logistics Services Ltd | Wholesale & retail | 2010 |
| Intelisense Group Ltd | Financial services | 2018 |
| Intelisense Holdings Limited | Real estate | 2017 |
| Intelisense IT Limited | Information & communication | 2010 |
| Intelisense Property Ltd | Real estate | 2021 |
| Intelisense Services Ltd | Information & communication | 2019 |
| Intelisense Software Ltd | Information & communication | 2018 |
| Intelligence HR Solutions Ltd | Administrative & support | 2019 |
| Intelligent Bloom Ltd | Real estate | 2025 |
| Intelligent Lighting Ltd | Arts & recreation | 2022 |
| Intelligent Music Limited | Education | 1996 |
| Intelliseek Ltd | Professional & scientific | 2014 |
| Inter City System Ltd | Construction | 2016 |
| Interact Recruitment Solutions Limited | Administrative & support | 2010 |
| Interactive Advisory Limited | Other services | 2014 |
| Interactive Education Systems Limited | Education | 2025 |
| Intercare Healthcare Solutions Limited | Administrative & support | 2024 |
| Interclass Construction Services PLC | Construction | 2000 |
| Interclass Holdings Limited | Administrative & support | 1976 |
| Interclass Public Limited Company | Construction | 1988 |
| Intercounty Driveways Ltd | Construction | 2025 |
| Interest Free Carpets Limited | Wholesale & retail | 2024 |
| Interface Strategic Solutions Ltd | Financial services | 2014 |
| Interfaith Wolverhampton | Education | 1996 |
| Interhaze Contracts Limited | Administrative & support | 2021 |
| Interhaze HR2 Ltd | Administrative & support | 2020 |
| Interior Service Holdings Limited | Construction | 2016 |
| Interiors Direct Operations Limited | Manufacturing | 2025 |
| Interiors Game Ltd | Construction | 2024 |
| Interlaxy Limited | Wholesale & retail | 2026 |
| Internal Accounts Payroll Ltd | Administrative & support | 2023 |
| International Commercial Funding Solutions Limited | Financial services | 2009 |
| International Education and Training Solutions Ltd | Professional & scientific | 2013 |
| International Insignia Limited | Wholesale & retail | 2006 |
| International Pipeline Structural Solutions Limited | Mining & quarrying | 2014 |
| International Recruitment Agents Ltd | Wholesale & retail | 2016 |
| Intervision Management Limited | Professional & scientific | 2015 |
| Intouch Building Services Ltd | Construction | 2021 |
| Intracom Consulting Limited | Extraterritorial | 1999 |
| Intrapine Limited | Construction | 2018 |
| Intrico Ltd | Wholesale & retail | 2022 |
| Intrinsic Estate Planning Ltd | Professional & scientific | 2025 |
| Intrinsic Financial Ltd | Professional & scientific | 2024 |
| Intrinsic Tax Advisory Ltd | Professional & scientific | 2025 |
| Introspective Productions Ltd | Information & communication | 2023 |
| Intsol Payroll Ltd | Administrative & support | 2017 |
| Invest and Consult Limited | Professional & scientific | 2015 |
| Invest Return Limited | Real estate | 2022 |
| Invest-Amor Ltd | Real estate | 2019 |
| Investments 1819 Ltd | Real estate | 2024 |
| Investra AI Limited | Information & communication | 2025 |
| Invictex Ltd | Professional & scientific | 2023 |
| Invictus Active Limited | Manufacturing | 2022 |
| Invigorate Womens Wellness Limited | Other services | 2024 |
| Inwork Ltd | Construction | 2020 |
| Ioan Ltd | Transport & logistics | 2022 |
| Ioan Moales Ltd | Transport & logistics | 2016 |
| IOK Solutions Ltd | Wholesale & retail | 2025 |
| Iolite Properties Ltd | Real estate | 2025 |
| ION Cars Services Ltd | Manufacturing | 2016 |
| Ionel Driving Limited | Transport & logistics | 2018 |