| Invigorate UK Limited | Professional & scientific | 1998 |
| Invincible IT Solutions Ltd | Information & communication | 2016 |
| Invitation Hub Limited | Manufacturing | 2024 |
| Involution Limited | Manufacturing | 1999 |
| Involution Store Ltd | Wholesale & retail | 2020 |
| Involve Leeds | Education | 2015 |
| Involved Social Impact Projects Limited | Education | 2018 |
| INW Investments Ltd | Real estate | 2012 |
| Inward Revenue Consulting Ltd | Administrative & support | 2007 |
| Inyasha Awesome Limited | Health & social care | 2018 |
| Inzpired Properties Limited | Real estate | 2016 |
| INZUZ0 Engage Ltd | Professional & scientific | 2021 |
| Inzuzo Ltd | Financial services | 2015 |
| Inzys Health Ltd | Wholesale & retail | 2024 |
| IO Outsourcing Limited | Financial services | 2014 |
| Ioan Acatrinei Ltd | Transport & logistics | 2025 |
| Ioan Balica Delivery Ltd | Transport & logistics | 2025 |
| Ioanninalake Ltd | Hospitality | 2025 |
| IOC Leeds Ltd | Hospitality | 2022 |
| IOI Systems Ltd | Wholesale & retail | 2019 |
| ION Body Limited | Arts & recreation | 2021 |
| ION Frasinel Limited | Transport & logistics | 2025 |
| Iona Publishing Ltd | Information & communication | 2015 |
| Ionell Fixing Ltd | Construction | 2010 |
| Ionfconstruction Ltd | Construction | 2025 |
| Ionic Security Systems Limited | Administrative & support | 2022 |
| Ionis Design Ltd | Professional & scientific | 2025 |
| Ionix Advanced Technologies Ltd | Professional & scientific | 2011 |
| Ionlooker Ltd | Manufacturing | 2019 |
| Ionut Alexandriuc Limited | Transport & logistics | 2026 |
| Ionut B&R Ltd | Administrative & support | 2025 |
| Ionut K Ltd | Transport & logistics | 2021 |
| Ionut Negoita Ltd | Transport & logistics | 2025 |
| Ionutnana Ltd | Transport & logistics | 2025 |
| Ioro Demolition Services Ltd | Construction | 2025 |
| Iosif BJN Ltd | Transport & logistics | 2025 |
| Iosif Ciobotaru Limited | Transport & logistics | 2025 |
| Iota Business Limited | Professional & scientific | 2003 |
| Iota TAU Ltd | Information & communication | 1995 |
| Iotera Systems Limited | Information & communication | 2025 |
| Iovation Limited | Information & communication | 2015 |
| Iowa Debtco Limited | Administrative & support | 2022 |
| IP Leaflets Distribution Limited | Administrative & support | 2024 |
| IP Project Delivery Ltd | Professional & scientific | 2026 |
| IPC Fixings Limited | Administrative & support | 2002 |
| IPC Industrial Limited | Wholesale & retail | 2017 |
| Ipeek Limited | Information & communication | 2012 |
| Ipex Technologies Limited | Information & communication | 2019 |
| IPF Development (2003) Limited | Administrative & support | 2003 |
| IPF Digital Group Limited | Financial services | 2006 |
| IPF Financial Services Limited | Administrative & support | 2002 |
| IPF Financing 2 Limited | Financial services | 2025 |
| IPF Financing Limited | Financial services | 2003 |
| IPF Holdings Limited | Professional & scientific | 1980 |
| IPF International Limited | Administrative & support | 1963 |
| IPF Loan Financing Ltd | Financial services | 2023 |
| IPF Nordic Limited | Financial services | 2018 |
| IPF Pension Trustee Limited | Financial services | 2007 |
| IPH Realisations 2025 Limited | Professional & scientific | 2011 |
| IPH Trade Ltd | Wholesale & retail | 2024 |
| Ipharm Solutions Ltd | Administrative & support | 2007 |
| Ipharma 2 Ltd | Wholesale & retail | 2014 |
| Ipharma Ltd | Health & social care | 2010 |
| Iphone Corner Ltd | Wholesale & retail | 2025 |
| Iphone Repair Leeds Ltd | Wholesale & retail | 2024 |
| IPI Group Holdings Limited | Financial services | 2025 |
| IPI Homes Limited | Construction | 2025 |
| Ipi-Uk Ltd | Real estate | 2025 |
| Ipih Realisations 2025 Limited | Professional & scientific | 1984 |
| IPL (Leeds) Limited | Construction | 2021 |
| IPL Property Management Ltd | Real estate | 2022 |
| IPR Coatings Ltd | Construction | 2026 |
| Iproperty Ltd | Real estate | 2015 |
| IPS Property Holdings Limited | Financial services | 2019 |
| Ipsilon Ltd | Wholesale & retail | 2024 |
| Ipsosolo Limited | Other services | 2009 |
| Ipunkt Ltd | Wholesale & retail | 2021 |
| IQ Acquisition Management Ltd | Financial services | 2022 |
| IQ Automation Ltd | Information & communication | 2016 |
| IQ Blinds Ltd | Manufacturing | 2023 |
| IQ Labs AO Ltd | Wholesale & retail | 2023 |
| IQ Law Limited | Professional & scientific | 2016 |
| IQ Lets Ltd | Real estate | 2024 |
| IQ Properties (Leeds) Ltd | Real estate | 2026 |
| IQ Strengthened Limited | Hospitality | 2026 |
| IQM Accountants Ltd | Professional & scientific | 2025 |
| Iqob Holding Ltd | Financial services | 2022 |
| Iqob Managed Services Ltd | Professional & scientific | 2023 |
| Iqra Driving School Ltd | Education | 2025 |
| Iqus Limited | Information & communication | 2000 |
| IQW Developments Limited | Real estate | 2021 |
| IQW Plus Ltd | Construction | 2022 |
| IR77 Limited | Information & communication | 2018 |
| Irad Healthcare Ltd | Health & social care | 2025 |
| Iram Rashid Ltd | Health & social care | 2019 |
| Iram Shelton Limited | Professional & scientific | 2022 |
| Irasna Trading Limited | Wholesale & retail | 2018 |
| IRC Group - Facility's Management Solutions Ltd | Construction | 2026 |
| IRC Group - Mechanical and Electrical Solutions Ltd | Construction | 2024 |
| IRC Group Holdings Ltd | Construction | 2026 |