| I&T Property Investments Ltd | Other services | 2010 |
| I-Lite Limited | Professional & scientific | 2003 |
| I-Putt Ltd | Manufacturing | 2011 |
| I. W. S. Limited | Professional & scientific | 1984 |
| I.D.M Joinery Ltd | Construction | 2004 |
| I.D.M. Holdings Limited | Professional & scientific | 2015 |
| I.J. 2004 Limited | Financial services | 2004 |
| I.M.I Products Limited | Manufacturing | 2005 |
| I2SQUARED Ltd | Transport & logistics | 2021 |
| Iaag Limited | Professional & scientific | 2005 |
| IAB Barber Shop Ltd | Other services | 2024 |
| Iacafm Limited | Professional & scientific | 2011 |
| IAG4U Limited | Extraterritorial | 2013 |
| Iain Ferguson Risk Advisory Limited | Professional & scientific | 2024 |
| Iain Longworth Partnership Limited | Financial services | 2014 |
| IAN Bradley Construction Limited | Construction | 2015 |
| IAN Brownrigg Limited | Construction | 2004 |
| IAN Charles Salon Limited | Wholesale & retail | 2003 |
| IAN Collins Automotive Limited | Wholesale & retail | 2019 |
| IAN Haydock Limited | Other services | 2002 |
| IAN Mace Construction Management Limited | Construction | 2014 |
| IAN Robinson Transport Limited | Transport & logistics | 2013 |
| IAN Sabey Accountancy Services Ltd | Professional & scientific | 2012 |
| IAN Wells Joinery Limited | Construction | 2008 |
| IAN Whitehead Limited | Construction | 2020 |
| IAN Wilde Independent Funeral Directors Limited | Other services | 2013 |
| IAN Wilkinson Building & Renovation Ltd | Construction | 2023 |
| IAN Woodburn Limited | Wholesale & retail | 2009 |
| Ianj Ltd | Financial services | 2024 |
| Ianna Group Ltd | Financial services | 2022 |
| Iatham International Limited | Other services | 2025 |
| Iatqb Ltd | Education | 2019 |
| IB Enterprises (UK) Ltd | Wholesale & retail | 2003 |
| IB Trading (NW) Limited | Wholesale & retail | 2024 |
| Iber Supplies Limited | Wholesale & retail | 2013 |
| Ibim Limited | Professional & scientific | 2024 |
| Ibluehome Ltd | Wholesale & retail | 2014 |
| IBP Architecture Ltd | Professional & scientific | 2020 |
| Ibridge Solutions Limited | Information & communication | 2008 |
| Icacl Holdings Limited | Professional & scientific | 2015 |
| Icancheck Ltd | Information & communication | 2023 |
| Icarus Distribution Ltd | Wholesale & retail | 2024 |
| Icase Ltd | Wholesale & retail | 2018 |
| ICC Marketing Ltd | Professional & scientific | 2025 |
| Iceberg Trading Ltd | Wholesale & retail | 2025 |
| Iced Kandy Ltd | Wholesale & retail | 2024 |
| Icewerx Ltd | Wholesale & retail | 2026 |
| ICG Holdings Preston Limited | Financial services | 2025 |
| ICL Corporate Limited | Extraterritorial | 2015 |
| Icon Horseboxes Limited | Manufacturing | 2014 |
| ICS Online Ltd | Wholesale & retail | 2009 |
| ICT Direct Ltd | Information & communication | 2007 |
| ICT Holdings Limited | Information & communication | 2008 |
| ID Academy Ltd | Education | 2023 |
| ID Corporate Consultants Ltd | Professional & scientific | 2024 |
| ID8 Group Limited | Professional & scientific | 2022 |
| IDC Business Communications Limited | Professional & scientific | 2007 |
| Iddon Ecom Ltd | Wholesale & retail | 2024 |
| Iddon GAS and Solid Fuel Services Ltd | Construction | 2019 |
| Iddon General Renovations Ltd | Construction | 2024 |
| Ideal Driveways and Patios Ltd | Construction | 2026 |
| Ideal Interiors (North West) Limited | Wholesale & retail | 2004 |
| Ideal Living Property Limited | Real estate | 2018 |
| Ideal Sales Solutions Ltd | Information & communication | 2008 |
| Ideal Trade Centre (NW) Limited | Wholesale & retail | 2008 |
| Ideals (NW) Ltd | Other services | 2015 |
| Iden Limited | Transport & logistics | 2016 |
| Identity Alchemy Limited | Health & social care | 2025 |
| IE LOC Ltd | Health & social care | 2025 |
| Iegroupuk Ltd | Financial services | 2018 |
| Ifav Ventures Limited | Administrative & support | 2021 |
| Ifika Solutions Ltd | Information & communication | 2021 |
| Ifor Williams Manufacturer Limited | Manufacturing | 2025 |
| Iftikhar Uddin Limited | Real estate | 2012 |
| Igen Dent Ltd | Health & social care | 2011 |
| IGK a Ltd | Wholesale & retail | 2023 |
| Ignite Heating & GAS Ltd | Construction | 2025 |
| IGR Holdings Ltd | Financial services | 2022 |
| IH Consumer Health Limited | Financial services | 2026 |
| IH News Limited | Wholesale & retail | 2013 |
| IH1 Limited | Financial services | 2024 |
| IH2 Limited | Financial services | 2024 |
| IH5 Limited | Financial services | 2026 |
| IHI Group Ltd | Hospitality | 2019 |
| IHI Holdings Ltd | Real estate | 2022 |
| IHM Accountant Solutions Ltd | Financial services | 2022 |
| Iiza Books and Consultancy Ltd | Professional & scientific | 2022 |
| IJS Consulting Limited | Information & communication | 2009 |
| Ijst Ltd | Real estate | 2023 |
| IJW Interim Management & Consulting Ltd | Professional & scientific | 2025 |
| IJW Limited | Professional & scientific | 2020 |
| IKD Transport Ltd | Transport & logistics | 2024 |
| IKE & Chad Limited | Other services | 2018 |
| Ikigaailondon Ltd | Wholesale & retail | 2025 |
| IKM Media Limited | Information & communication | 2020 |
| IL Castello J Ltd | Hospitality | 2025 |
| IL Gusto D'Italia (Bamber Bridge) Limited | Hospitality | 2018 |
| IL Squared Limited | Hospitality | 2018 |
| Iland Victoria Properties Limited | Real estate | 2017 |
| Ilashedpro Ltd | Wholesale & retail | 2022 |