| Ideal Alarms & Cctv Limited | Administrative & support | 2014 |
| Ideal Couriers Ltd | Transport & logistics | 2021 |
| Ideal Driveways & Roofing Solutions Ltd | Construction | 2025 |
| Ideal Emergency Plumbers Limited | Construction | 2024 |
| Ideal Form Contracts UK Ltd | Construction | 2019 |
| Ideal Products Ltd | Wholesale & retail | 2010 |
| Ideasfit Marketing Ltd | Wholesale & retail | 2025 |
| Idehien Limited | Wholesale & retail | 2017 |
| Iden Consulting Technology Limited | Wholesale & retail | 2025 |
| Idex Global Property Limited | Hospitality | 2024 |
| IDM Creative LLP | | 2015 |
| IDM Design Limited | Professional & scientific | 2013 |
| Idmdrv Ltd | Transport & logistics | 2025 |
| Idyl Occasions Limited | Other services | 2012 |
| Iehsas Global Limited | Professional & scientific | 2024 |
| Iffy Fadez Ltd | Other services | 2025 |
| Ifordable Ltd | Wholesale & retail | 2025 |
| Iftikhar Ahmed Trading Ltd | Financial services | 2023 |
| IFW - Smaller Loans LP | | 2023 |
| IG Financial Services Ltd | Financial services | 2023 |
| Igaf Worldwide Europe Limited | Extraterritorial | 2012 |
| IGN Ltd | Real estate | 2022 |
| IGN Properties Ltd | Real estate | 2022 |
| Ignis Sonus Ltd | Construction | 2023 |
| Ignite Learning Partnership | Education | 2017 |
| Ignite Your Health Community Interest Company | Health & social care | 2023 |
| IHA Property Consultancy Ltd | Construction | 2025 |
| Ihauser Ltd | Professional & scientific | 2018 |
| Ihomes Estates Limited | Real estate | 2014 |
| Ijay Limited | Wholesale & retail | 2022 |
| IJM Fire Systems (UK) Limited | Extraterritorial | 2007 |
| IJM Limited | Real estate | 2024 |
| IJN Holdings Ltd | Real estate | 2024 |
| IJS Evolution Projects Ltd | Real estate | 2017 |
| IK Cleaning Limited | Administrative & support | 2026 |
| IK Transport Service Ltd | Other services | 2025 |
| Ikebube Investment Limited | Health & social care | 2022 |
| Ikecondy Divine Limited | Administrative & support | 2014 |
| Ikedec Limited | Wholesale & retail | 2017 |
| Ikedec Plus Limited | Wholesale & retail | 2019 |
| Ikhwa Builders Ltd | Manufacturing | 2026 |
| Ikloan Engineering Solutions Limited | Construction | 2014 |
| Ikoyi Chapmans Limited | Manufacturing | 2015 |
| Ikoyi Holdings Limited | Financial services | 2018 |
| Ilashboutique Ltd | Other services | 2023 |
| ILH Investment Holdings Limited | Real estate | 2025 |
| Ilie Ghivea Limited | Wholesale & retail | 2026 |
| Illuminate Construction Limited | Manufacturing | 2014 |
| Illuminatek Ltd | Education | 2022 |
| Ilmexpress Ltd | Transport & logistics | 2023 |
| Ilya 110 Ltd | Wholesale & retail | 2025 |
| Ilyas Ahmad Ltd | Wholesale & retail | 2025 |
| Imac Properties Limited | Real estate | 2024 |
| Image Blinds Limited | Administrative & support | 2016 |
| Image Squad Limited | Professional & scientific | 2019 |
| Imagine Arts Limited | Arts & recreation | 2019 |
| Imagine LAB Education Ltd | Agriculture & fishing | 2023 |
| Imagine Modular Ltd | Construction | 2022 |
| Imagine Property Holdings (2020) Ltd | Financial services | 2020 |
| Imakfilms Ltd | Information & communication | 2014 |
| Imas Global Ltd | Real estate | 2025 |
| IMC Couriers Ltd | Transport & logistics | 2022 |
| Imdee. Ltd | Education | 2026 |
| Imex Cafe Ltd | Hospitality | 2023 |
| IMF Restoration Services Ltd | Wholesale & retail | 2011 |
| IMI Logistics Ltd | Transport & logistics | 2026 |
| Immaculate Consulting Limited | Information & communication | 2020 |
| Immaculate Sparkle Cleaning Services Ltd | Administrative & support | 2023 |
| Immigration Help Limited | Professional & scientific | 2023 |
| Impact Training and Development Consultancy Limited | Education | 2017 |
| Impct Augusta Limited | Real estate | 2026 |
| Impct Developments Limited | Real estate | 2025 |
| Impct Dudley Limited | Real estate | 2026 |
| Imperial Care Provider Ltd | Health & social care | 2019 |
| Imperial Commercial Holdings Limited | Real estate | 2022 |
| Imperial Law Limited | Professional & scientific | 2010 |
| Imperial Marketing UK Limited | Wholesale & retail | 2008 |
| Imperial Properties Limited | Real estate | 2022 |
| Imperial Property SPV Limited | Real estate | 2018 |
| Imperial WOK (W-Ton) Ltd | Hospitality | 2021 |
| Imperium Lettings Limited | Real estate | 2025 |
| Imperra Limited | Real estate | 2025 |
| Impervious Property Limited | Real estate | 2023 |
| IMS Properties and Investments Ltd | Real estate | 2021 |
| Imtisal Traders Ltd | Wholesale & retail | 2025 |
| IN Abundance Care Ltd | Agriculture & fishing | 2023 |
| IN Carriers Ltd | Transport & logistics | 2026 |
| IN Hand Property Management Ltd | Real estate | 2020 |
| IN the Middle Limited | Professional & scientific | 2022 |
| IN2 3D Limited | Professional & scientific | 2012 |
| Inal (2020) Limited | Other services | 2020 |
| Inatural Ltd | Manufacturing | 2023 |
| Inbal Valves UK Limited | Wholesale & retail | 2008 |
| Incise Academy CIC | Education | 2024 |
| Incise Cosmetics Ltd | Other services | 2023 |
| Include ME TOO | Health & social care | 2006 |
| Inclusive Mind Works Ltd | Health & social care | 2024 |
| Increasingly UN Limited | Information & communication | 2014 |
| IND Capital Ltd | Financial services | 2024 |
| Indasol Holdings Limited | Financial services | 2026 |