| Ice Investments (G.B.) LLP | | 2008 |
| Ice Spa Limited | Health & social care | 2014 |
| Iceblue Utilities Ltd | Construction | 2023 |
| Ichor Investments Limited | Real estate | 2019 |
| Ickenham Harbour Ltd | Hospitality | 2026 |
| Icknox Limited | Wholesale & retail | 2015 |
| ICM Electrics Limited | Construction | 2019 |
| ICO (Sales) Limited | Wholesale & retail | 2018 |
| ICO Logistics Limited | Construction | 2021 |
| Iconic Time Limited | Wholesale & retail | 2020 |
| Iconique Corporate Gifting Ltd | Professional & scientific | 2025 |
| Icontrol Hospitality Ltd | Wholesale & retail | 2002 |
| Icu-Reset Ltd | Information & communication | 2024 |
| ICY Green Ltd | Wholesale & retail | 2016 |
| IDA Solutions Limited | Real estate | 2021 |
| Idea HAT Productions Limited | Professional & scientific | 2017 |
| Ideabox Creative Factory Ltd | Professional & scientific | 2014 |
| Ideal Accommodation Limited | Real estate | 2023 |
| Ideal Europe Brands Ltd | Wholesale & retail | 2024 |
| Ideal Planning and Design Limited | Professional & scientific | 2012 |
| Ideal Souvenirs Limited | Wholesale & retail | 2023 |
| Idealoption Property Management Limited | Real estate | 1991 |
| Idenbury Court Maintenance Company Limited | Real estate | 1967 |
| IDV Construction Ltd | Construction | 2024 |
| IEP Bricklayering Ltd | Construction | 2026 |
| IF and Then C.I.C. | Administrative & support | 2015 |
| Ifix London Ltd | Other services | 2023 |
| Ifix Mobile Tyres Ltd | Wholesale & retail | 2025 |
| Ifix Tyre Garage Ltd | Wholesale & retail | 2026 |
| Ifix Tyres Ltd | Wholesale & retail | 2025 |
| IG Investments (London) Limited | Real estate | 2025 |
| Igdp Holdings Limited | Financial services | 2025 |
| IGI Principal Investments Limited | Real estate | 2020 |
| Ignis Protect Ltd | Construction | 2021 |
| IH Sunshine Limited | Administrative & support | 2024 |
| IKA Property & Investments Ltd | Real estate | 2018 |
| Ikigai Dental Limited | Health & social care | 2023 |
| Ikigai Ember Estates Ltd | Construction | 2025 |
| Ikos Assets Limited | Real estate | 2017 |
| Ikram & Sons Limited | Wholesale & retail | 2022 |
| Ikshana Management Company Limited | Professional & scientific | 2023 |
| Il&Fs Global Financial Services (UK) Ltd. | Financial services | 2009 |
| Ilba Electrics Limited | Construction | 2012 |
| Illyrian Cleaning Services Ltd | Administrative & support | 2026 |
| Ilson Limited | Professional & scientific | 2006 |
| IM IT Media Limited | Information & communication | 2023 |
| Imaan Airport Transportation Ltd | Transport & logistics | 2025 |
| Imagine Croydon Limited | Real estate | 2015 |
| Imaisa Windows &Doors Ltd | Manufacturing | 2025 |
| Iman Auto Services Ltd | Wholesale & retail | 2025 |
| Imani SEM Limited | Arts & recreation | 2014 |
| Imeus Communications Limited | Professional & scientific | 2016 |
| IMG Railway Limited | Construction | 2018 |
| Imlet Limited | Professional & scientific | 2010 |
| IMM Express Ltd | Construction | 2018 |
| Imness Estates LLP | | 2017 |
| Imob Construction Ltd | Construction | 2013 |
| Impact Lens Financial Planning Limited | Professional & scientific | 2021 |
| Impact Lens Ltd | Professional & scientific | 2018 |
| Impact Technology Solutions Ltd | Information & communication | 2023 |
| Imperial Edge Ltd | Education | 2026 |
| Imperial World Travel Ltd | Administrative & support | 2010 |
| Imperium Motors Limited | Wholesale & retail | 2025 |
| Imposter Syndrome Entertainment Ltd | Hospitality | 2022 |
| Impressario Ltd | Other services | 2014 |
| Imprinted Doroo Ltd | Construction | 2024 |
| Imtiazehmad Ltd | Construction | 2025 |
| IN Bloom Industries Ltd. | Real estate | 2015 |
| Inagio Limited | Wholesale & retail | 2022 |
| Incredible Minds Limited | Information & communication | 2014 |
| Incredible Ventures Limited | Information & communication | 2019 |
| Inday's Mabuhay Mart Ltd | Wholesale & retail | 2026 |
| Index Assets and Consulting Ltd | Construction | 2009 |
| India Knowledge Consortium Ltd | Professional & scientific | 2021 |
| Indian Funeral Directors Limited | Other services | 2002 |
| Indian Funeral Services Limited | Other services | 2016 |
| Indigo Property Partners Ltd | Real estate | 2017 |
| INDIGO1000 Ltd | Professional & scientific | 2019 |
| Indrakumaran Limited | Professional & scientific | 2024 |
| Inert Soil Management Limited | Construction | 2007 |
| Infantry Scaffolding Ltd | Construction | 2018 |
| Infill Limited | Real estate | 2005 |
| Infilogi Ltd | Information & communication | 2024 |
| Infinite Mind Ltd | Health & social care | 2016 |
| Infiniti Capital LLP | | 2014 |
| Infinitrim Ltd | Arts & recreation | 2018 |
| Infinity AV Ltd | Construction | 2018 |
| Infinity H Ltd | Financial services | 2022 |
| Infinity Measures Limited | Professional & scientific | 2025 |
| Infinity Nest Property Ltd | Real estate | 2022 |
| Infinity Options Limited | Professional & scientific | 2017 |
| Infinity Property Renovation Solutions Ltd | Construction | 2024 |
| Infinity Windows & Doors Ltd | Construction | 2025 |
| Infomex Limited | Extraterritorial | 2005 |
| Infrasphere Ltd | Information & communication | 2026 |
| Infronte Ltd | Information & communication | 2026 |
| Infyesys International Limited | Information & communication | 1999 |
| Ingenuity Globalnet Limited | Construction | 2025 |
| Ingravia Ltd | Wholesale & retail | 2017 |
| Inkasec Ltd | Information & communication | 2017 |