| Imar Properties Ltd | Real estate | 2023 |
| IMB Brickwork Limited | Construction | 2018 |
| IMB Consulting Limited | Real estate | 2004 |
| IMC Construction Services Limited | Construction | 2018 |
| IMD Consultants Ltd | Professional & scientific | 2021 |
| Imdi London Limited | Wholesale & retail | 2023 |
| Imend Gadgets Limited | Wholesale & retail | 2019 |
| Imer Care Solutions Limited | Administrative & support | 2007 |
| Imeraj Properties Ltd | Real estate | 2025 |
| IMH Property Consultants Limited | Transport & logistics | 2017 |
| IMH Property Ltd | Real estate | 2025 |
| IMH Utilities Ltd | Construction | 2023 |
| IMI Hydronic Engineering Limited | Construction | 1994 |
| IMJ Consultancy Limited | Other services | 2025 |
| Imjstone Ltd | Construction | 2020 |
| Immaculate Decorators Service Ltd | Other services | 2009 |
| Immaculate Finish Decor Ltd | Construction | 2021 |
| Immersive Horizons Ltd | Professional & scientific | 2023 |
| Immersive Nexus Ltd | Professional & scientific | 2025 |
| Immzi Company Ltd | Wholesale & retail | 2017 |
| Imobile Fixer Ltd | Wholesale & retail | 2024 |
| Imotors Auto Limited | Wholesale & retail | 2018 |
| Imotrea Construction Ltd | Construction | 2021 |
| Impact Designs Group Limited | Professional & scientific | 2019 |
| Impact Gospel Centre | Other services | 2010 |
| Impact Wealth Solutions Limited | Financial services | 2016 |
| Impellam Group Limited | Administrative & support | 2008 |
| Impellam Holdings Limited | Professional & scientific | 1951 |
| Impellam UK Limited | Professional & scientific | 2009 |
| Imperial Books Ltd | Manufacturing | 2023 |
| Imperial Court Management (Luton) Limited | Households | 2007 |
| Imperial Executive Travel Ltd | Transport & logistics | 2025 |
| Imperial Home Renovations Ltd | Construction | 2023 |
| Imperial MK Limited | Real estate | 2020 |
| Imperial Portfolios Limited | Real estate | 1997 |
| Imperial Residence Group Ltd | Real estate | 2026 |
| Imperial Trade Specialists Ltd | Wholesale & retail | 2016 |
| Imperial Transport Luton Ltd | Transport & logistics | 2019 |
| Impress Logistics Ltd | Transport & logistics | 2022 |
| Imran Khan 804 Ltd | Wholesale & retail | 2024 |
| Imran Mobile Services Ltd | Wholesale & retail | 2024 |
| Imre Treats Limited | Wholesale & retail | 2022 |
| Imtiaz & Co Accountants Limited | Professional & scientific | 2019 |
| IN a Nutshell Creative Ltd | Professional & scientific | 2018 |
| IN a Wish Ltd | Wholesale & retail | 2011 |
| IN Jesus Name CIC | Other services | 2024 |
| IN Vogue Designs Ltd | Manufacturing | 2024 |
| IN2UK Imports Ltd | Wholesale & retail | 2025 |
| INA Holdings Ltd | Financial services | 2020 |
| Inayya Corp Ltd | Hospitality | 2017 |
| Inbrella Limited | Professional & scientific | 2012 |
| Incentre Ltd | Wholesale & retail | 2013 |
| Inception Cleaners Ltd | Administrative & support | 2021 |
| Inclination Limited | Information & communication | 2020 |
| Incog Solutions Ltd | Administrative & support | 2025 |
| Inconstruct Engineering Ltd | Construction | 2022 |
| Indeed Cars Ltd | Wholesale & retail | 2022 |
| Independent Broadcasting Network Limited | Administrative & support | 2018 |
| Independent Commercial Environments Ltd | Construction | 2013 |
| Independent Home Care Ltd | Health & social care | 2016 |
| Independents Together Ltd | Professional & scientific | 2019 |
| Indepthcare Ltd | Wholesale & retail | 2022 |
| Inder Constructions Ltd | Construction | 2019 |
| Indiabulls Ltd | Agriculture & fishing | 2019 |
| Indian Chomok Group Ltd | Hospitality | 2025 |
| Indian Chowrasta Ltd | Hospitality | 2026 |
| Indian Meal Limited | Hospitality | 2018 |
| Indian Ocean Beds Ltd | Hospitality | 2018 |
| Indian Ocean Exclusive Ltd | Hospitality | 2022 |
| Indian Signature Restaurants Ltd | Hospitality | 2008 |
| Indigenous People | Education | 1997 |
| Indigo Gardens Management Company Ltd | Households | 2018 |
| Indigo Inn Limited | Hospitality | 2024 |
| Indigo Land and New Homes Ltd | Real estate | 2019 |
| Indigo Residential Developments Limited | Construction | 2017 |
| Indigo Residential Limited | Real estate | 2005 |
| Indigo Tiger Limited | Wholesale & retail | 2000 |
| Indo Retrofit Solutions Limited | Professional & scientific | 2026 |
| Indus Construction Ltd | Construction | 2018 |
| Indus Smart Solutions Ltd | Extraterritorial | 2021 |
| Indus Valley Services Ltd | Information & communication | 2026 |
| Industrial Outsourcing Project Management UK Ltd | Wholesale & retail | 2025 |
| Industrial Sound Light & Stage Ltd | Arts & recreation | 2023 |
| Ineedcleaner Ltd | Administrative & support | 2025 |
| Infaleo Solutions Ltd | Information & communication | 2025 |
| Infantasia Ltd | Arts & recreation | 2022 |
| Inferno Enterprises Limited | Wholesale & retail | 2025 |
| Infinite Haven Care Ltd | Health & social care | 2024 |
| Infinite Residences Limited | Real estate | 2026 |
| Infiniti Ltd | Transport & logistics | 2024 |
| Infiniti Solutions Ltd | Wholesale & retail | 2024 |
| Infinitum Soft Technologies Ltd | Wholesale & retail | 2024 |
| Infinity Batteries Limited | Wholesale & retail | 2021 |
| Infinity Building Solutions Limited | Construction | 2013 |
| Infinity Care HBB Ltd | Public administration | 2024 |
| Infinity Careers Ltd | Administrative & support | 2025 |
| Infinity Court Ltd | Professional & scientific | 2016 |
| Infinity Divine Ltd | Arts & recreation | 2026 |
| Infinity Enterprises Trading Limited | Construction | 2021 |
| Infinity Finds Market Ltd | Wholesale & retail | 2026 |