| Ifmiafacilities Ltd | Construction | 2025 |
| IFR Automotive Vehicles Ltd | Wholesale & retail | 2025 |
| Iftikhar & Sons Ltd | Wholesale & retail | 2021 |
| Iglesia DE Dios Ministerio Internacional Manantial DE Bendición CIC | Other services | 2024 |
| Ignite GAS Services Inc Ltd | Construction | 2011 |
| Ignite Investments Yorkshire Limited | Financial services | 2025 |
| IH Driving School Limited | Education | 2023 |
| IH Enterprise Ltd | Construction | 2024 |
| IH Facilities Ltd | Transport & logistics | 2025 |
| IH Riders Ltd | Transport & logistics | 2024 |
| Ihear Limited | Professional & scientific | 2013 |
| Ihna Legal Ltd | Professional & scientific | 2022 |
| Ihome Technology Limited | Wholesale & retail | 2018 |
| II Pharma Ltd | Health & social care | 2024 |
| IJL Healthcare Ltd | Health & social care | 2021 |
| IK Properties Ltd | Real estate | 2024 |
| Ikew Education Ltd | Health & social care | 2023 |
| IKH Ltd | Professional & scientific | 2019 |
| Ikst Limited | Financial services | 2008 |
| IL Components Ltd | Wholesale & retail | 2022 |
| Ilanguages Limited | Education | 2008 |
| Illicit Risk Ltd | Wholesale & retail | 2024 |
| Illumina V Ltd | Hospitality | 2024 |
| Illustrators Company Ltd | Information & communication | 2025 |
| Ilsl Limited | Other services | 2015 |
| Iluiny Ltd | Wholesale & retail | 2025 |
| Ilyas Building Maintenance Ltd | Construction | 2025 |
| Imaan Grill House Ltd | Wholesale & retail | 2019 |
| Imagefuel Ltd | Information & communication | 2016 |
| Imagemaker (UK) Limited | Professional & scientific | 2002 |
| Imaginative Realities Limited | Information & communication | 2022 |
| IMG Fire & Security Ltd | Administrative & support | 2024 |
| Immer Vorne Ltd | Professional & scientific | 2026 |
| Immersion Sound Studio Limited | Information & communication | 2024 |
| Imoris Publishing Ltd | Information & communication | 2025 |
| Impact Accommodation Limited | Real estate | 2023 |
| Impact Bodyshop Specialists Ltd | Wholesale & retail | 2019 |
| Impact Education Multi Academy Trust | Education | 2013 |
| Impact Estates Ltd | Real estate | 2023 |
| Impact Maths Consultancy Ltd | Education | 2025 |
| Impact Prevention CIC | Education | 2024 |
| Imperial Bake House Limited | Wholesale & retail | 2015 |
| Imperial Capital Management (UK) Ltd | Real estate | 2024 |
| Imperial Gate Properties Limited | Real estate | 2025 |
| Imperial Investments & Properties Limited | Real estate | 1987 |
| Imperial Tiles Limited | Wholesale & retail | 2025 |
| Imperium 31 Ltd | Real estate | 2025 |
| Imperium Integration Ltd | Manufacturing | 2008 |
| Imperium REX Filing Solutions Ltd. | Hospitality | 2025 |
| Imperius Properties Ltd | Real estate | 2026 |
| Impo Tree Limited | Transport & logistics | 2016 |
| Impressions Contract Cleaning Ltd | Administrative & support | 2022 |
| Improved Athletic Clothing Ltd | Wholesale & retail | 2026 |
| Improved U Fitness Ltd | Arts & recreation | 2023 |
| Imran Food Store Limited | Wholesale & retail | 2025 |
| Imran Khan Medical Ltd | Health & social care | 2014 |
| Imran Pharmacare Ltd | Professional & scientific | 2015 |
| Imran Saeed Ltd | Health & social care | 2023 |
| Imran Ul-Haq Dentistry Ltd | Health & social care | 2010 |
| Imrans Takeaway Ltd | Hospitality | 2026 |
| IN Bloom Photography Ltd | Professional & scientific | 2020 |
| IN Construction Consulting Limited | Professional & scientific | 2016 |
| IN Good Company Beverages Ltd | Wholesale & retail | 2023 |
| IN the Distance Ltd | Wholesale & retail | 2025 |
| IN the Park Consulting Ltd | Professional & scientific | 2019 |
| IN2SWIM Ltd | Education | 2020 |
| Inara Locum Services Limited | Health & social care | 2024 |
| Incandescent Shine Ltd | Other services | 2019 |
| Inclusion Insights Group Ltd | Professional & scientific | 2023 |
| Inclusion Matters Ltd | Education | 2023 |
| Indcom Electrical Ltd. | Professional & scientific | 2010 |
| Independent Commercial Mortgages Limited | Financial services | 2008 |
| Independent Living Project Ltd | Health & social care | 2009 |
| Independent Security Trustee Limited | Administrative & support | 2017 |
| Independent Social Work Assessments Ltd | Health & social care | 2015 |
| Independent Transport Limited | Transport & logistics | 2019 |
| Indiano Balti Ltd | Hospitality | 2026 |
| Indicina Ltd | Information & communication | 2014 |
| Indigo Switch Ltd | Energy | 2024 |
| Indigo Trading Company Limited | Professional & scientific | 2002 |
| Indiway Deli Kitchen Ltd | Wholesale & retail | 2026 |
| Indulor UK Limited | Wholesale & retail | 2021 |
| Industrial Acoustic Solutions Ltd | Manufacturing | 2006 |
| Industrial and Construction Equipment Sales Limited | Transport & logistics | 1998 |
| Industrial Habitat Ltd | Manufacturing | 2021 |
| Industrial Relics Ltd | Wholesale & retail | 2023 |
| Inertia Corp Ltd | Wholesale & retail | 2023 |
| Infinite Creative Agency Ltd | Information & communication | 2023 |
| Infinite Explorer Ltd | Administrative & support | 2018 |
| Infinity Cube Europe Limited | Manufacturing | 2025 |
| Infinity Ledger and Legal Options Ltd | Professional & scientific | 2021 |
| Influx Appliances Limited | Wholesale & retail | 2018 |
| Infocor Limited | Information & communication | 2024 |
| Information Technology Experts UK Ltd | Information & communication | 2020 |
| Infranix Limited | Professional & scientific | 2025 |
| Ingenious 1964 Ltd | Construction | 2016 |
| Inglenook Investments Ltd | Real estate | 2026 |
| Initial Electrical Limited | Construction | 2014 |
| Initial Mechanical Limited | Construction | 2025 |
| Initial Properties Ltd | Real estate | 2023 |