| I&K Sons Services Limited | Transport & logistics | 2021 |
| I&L Investments Ltd | Real estate | 2023 |
| I&M Property Rentals Ltd | Real estate | 2021 |
| I&M Strategic Services Limited | Professional & scientific | 2025 |
| I&O Global Ltd | Information & communication | 2025 |
| I&Slettings Limited | Real estate | 2025 |
| I'D Curd That Ltd | Wholesale & retail | 2025 |
| I'M Proud of YOU Ltd | Wholesale & retail | 2021 |
| I-Crash Limited | Information & communication | 2021 |
| I-Nova Global Solutions (UK) Ltd | Wholesale & retail | 2022 |
| I.D. Podiatry Limited | Health & social care | 2010 |
| I.D.C. Belmont Limited | Information & communication | 1996 |
| I.M.W Engineered Solutions Ltd | Professional & scientific | 2020 |
| I.M.Y Pharma Limited | Health & social care | 2014 |
| I.S. Properties Limited | Real estate | 2010 |
| I2U Loyalty Ltd | Administrative & support | 2019 |
| IA Cardiology Ltd | Health & social care | 2025 |
| IA Health Ltd | Health & social care | 2025 |
| IA Trading Limited | Wholesale & retail | 2010 |
| IA2015 Designs Limited | Other services | 2024 |
| Iabc Ltd | Professional & scientific | 2012 |
| Iain Dowie Enterprises Limited | Information & communication | 2001 |
| Iain G DON Limited | Health & social care | 2021 |
| Iain Macdonald Catering Co Ltd | Hospitality | 2023 |
| Iainduncanconsult Limited | Professional & scientific | 2021 |
| Iamc Automotive Ltd | Wholesale & retail | 2025 |
| Iamdaani Ltd | Wholesale & retail | 2020 |
| IAN B. Edge Limited | Wholesale & retail | 2003 |
| IAN Brookes Building Contractors Limited | Construction | 2016 |
| IAN Crilly Plumbing, Heating & GAS Services Ltd | Construction | 2009 |
| IAN Hunter Media Limited | Information & communication | 2014 |
| IAN Laws Technical Management Services Limited | Professional & scientific | 2014 |
| IAN Smith Joiners Limited | Construction | 2001 |
| Ians Fish & Chips Limited | Hospitality | 2011 |
| IAP Procurement Limited | Administrative & support | 2015 |
| IAP Property Ltd | Real estate | 2025 |
| Iasb Group Ltd | Real estate | 2025 |
| IAW Investments Limited | Administrative & support | 2021 |
| Iawb Ltd | Manufacturing | 2020 |
| IAZ Investments Ltd | Wholesale & retail | 2015 |
| Iazm Properties Limited | Real estate | 2026 |
| IB Electrical (NW) Limited | Construction | 2017 |
| IB Goods Ltd | Wholesale & retail | 2023 |
| IB Mobile Valeting and Detailing Limited | Administrative & support | 2025 |
| IB Scaffolding Ltd | Construction | 2021 |
| IBA Properties Ltd. | Real estate | 2019 |
| Ibac Ltd | Information & communication | 2004 |
| Ibasis Limited | Wholesale & retail | 2008 |
| Ibbys Builders & Real State Ltd | Real estate | 2025 |
| IBC Joinery Limited | Construction | 2013 |
| Iberica Property Consultants Limited | Professional & scientific | 2015 |
| Ibez HD Limited | Transport & logistics | 2026 |
| Ibiza Final Boss Ltd | Arts & recreation | 2025 |
| Ibk-Fly Limited | Wholesale & retail | 2021 |
| IBL Commercial Limited | Information & communication | 2026 |
| IBL Productions Ltd | Extraterritorial | 2023 |
| IBL Ventures Limited | Financial services | 2025 |
| Ibolelo Holdings Limited | Other services | 2025 |
| Ibraheem (NW) Limited | Wholesale & retail | 2017 |
| Ibrahim Consultants Limited | Other services | 2014 |
| Ibrahim Validation Consulting Limited | Professional & scientific | 2022 |
| Ibrahmart Ltd | Wholesale & retail | 2024 |
| Ibrowse Consultancy Ltd | Information & communication | 2006 |
| Ican Properties Ltd | Real estate | 2025 |
| Icars INS Limited | Financial services | 2020 |
| Icasto Development Ltd | Information & communication | 2012 |
| ICC Group Limited | Transport & logistics | 2015 |
| Ice Enterprises Holdings Limited | Health & social care | 2017 |
| Ice Enterprises Properties Limited | Health & social care | 2017 |
| Ice Entertainment UK Ltd | Arts & recreation | 2009 |
| Ice Viking Limited | Wholesale & retail | 2024 |
| Ice Wizards Limited | Information & communication | 2009 |
| Ice-Edge Logistics Ltd | Transport & logistics | 2024 |
| Icegold Group Ltd | Wholesale & retail | 2024 |
| Icewyche Limited | Information & communication | 2005 |
| Icicledreams Ltd | Administrative & support | 2019 |
| Icirc Ltd | Professional & scientific | 2024 |
| ICJ Investments Limited | Administrative & support | 2020 |
| Iclaims Expert Limited | Professional & scientific | 2016 |
| Iclaims Medicals Limited | Health & social care | 2016 |
| Icompliance Group Ltd | Professional & scientific | 2019 |
| Icon Designs Limited | Manufacturing | 2002 |
| Iconic Perfumes Ltd | Wholesale & retail | 2023 |
| Iconic Recycling Bolton UK Limited | Water & waste | 2023 |
| Iconic Recycling Collections NW Ltd | Water & waste | 2023 |
| Iconiq Bathrooms Ltd | Wholesale & retail | 2019 |
| Icook Bolton Ltd | Hospitality | 2024 |
| ICP Accountancy Limited | Information & communication | 2015 |
| Icrit Healthcare Limited | Health & social care | 2014 |
| ICS Prestige Limited | Construction | 2014 |
| ICT (NW) Limited | Extraterritorial | 2014 |
| Ictuk Limited | Extraterritorial | 2020 |
| ID 01 Limited | Financial services | 2021 |
| ID Birdies Ltd | Wholesale & retail | 2026 |
| ID Holdco Limited | Financial services | 2023 |
| ID5 Limited | Other services | 2022 |
| Idea Labs Business Solutions Limited | Information & communication | 2014 |
| Ideal Aluminium Systems Ltd | Manufacturing | 2014 |
| Ideal Bizz Ltd | Wholesale & retail | 2024 |
| Ideal Business Services Limited | Information & communication | 2001 |