| Ilara Limited | Wholesale & retail | 2026 |
| ILC Construction Limited | Construction | 2019 |
| Ilead Education Centre Limited | Education | 2026 |
| Ilford Tea Rooms Ltd | Hospitality | 2019 |
| Ilic Ltd | Wholesale & retail | 2015 |
| Ilica Limited | Construction | 2018 |
| Iliffe and Sons Construction Ltd | Construction | 2024 |
| Iliffe Ltd | Wholesale & retail | 2016 |
| Iliffe Ward Ltd | Information & communication | 2000 |
| Ilimi Network Limited | Information & communication | 2025 |
| Ilixir Ltd | Wholesale & retail | 2022 |
| Iljk Ltd | Wholesale & retail | 2023 |
| Ilkeston Gains Ltd | Transport & logistics | 2014 |
| Ilkeston Homecare Limited | Health & social care | 2023 |
| ILL KID Records Ltd | Information & communication | 2023 |
| Ill-Gotten Gainz Ltd | Health & social care | 2026 |
| Illidge Consulting Limited | Professional & scientific | 2023 |
| Illington Select Ltd | Transport & logistics | 2014 |
| Illsley Holdings Limited | Other services | 2003 |
| Illston Authoring Limited | Arts & recreation | 2017 |
| ILLUMIN8 Blinds & Curtains Limited | Manufacturing | 2017 |
| ILLUMIN8 Holdings Limited | Other services | 2017 |
| ILLUMIN8 Products Limited | Financial services | 2023 |
| Illusion Cheer Academy Ltd | Arts & recreation | 2025 |
| ILM Investments Limited | Real estate | 2026 |
| ILM Works Ltd | Education | 2026 |
| Ilocate Properties Ltd | Real estate | 2015 |
| Ilovemybrands Limited | Wholesale & retail | 2025 |
| Ilovit Ltd | Information & communication | 2011 |
| ILP23 Ltd | Hospitality | 2023 |
| Ilsa Limited | Information & communication | 2025 |
| Ilsp Ltd. | Information & communication | 2017 |
| IM Advice Ltd | Professional & scientific | 2023 |
| IM Essential UK Ltd | Manufacturing | 2025 |
| IM25 Ltd | Professional & scientific | 2021 |
| IMA Trust | Education | 2023 |
| Imaan Investment Properties Limited | Real estate | 2025 |
| Imaani Holdings Ltd | Real estate | 2015 |
| Imacuo Ltd | Health & social care | 2022 |
| Imadari Ltd | Information & communication | 2022 |
| Image Cleaning Consultants Ltd | Administrative & support | 2015 |
| Image Hair & Beauty Salon Ltd | Other services | 2020 |
| Image in Mind Ltd | Administrative & support | 2003 |
| Image Interior Partitions Ltd | Construction | 2021 |
| Image Outerwear Limited | Manufacturing | 2000 |
| Image Principals Limited | Wholesale & retail | 2016 |
| Image Surgeons Limited | Extraterritorial | 2009 |
| Imagenova Limited | Information & communication | 2015 |
| Imageon Designs Limited | Administrative & support | 2009 |
| Imagepro Limited | Wholesale & retail | 2025 |
| Imaginarium Creations CIC | Information & communication | 2023 |
| Imagine Design Ltd | Manufacturing | 2011 |
| Imagine IF Limited | Education | 2017 |
| Imaginetek Limited | Information & communication | 2021 |
| Imah Properties Ltd | Real estate | 2020 |
| Imaks Style Ltd | Other services | 2016 |
| Imall ENT Ltd | Wholesale & retail | 2025 |
| Imam Consulting Limited | Professional & scientific | 2014 |
| Iman Mini Market Limited | Wholesale & retail | 2022 |
| Iman Supermarket Limited | Wholesale & retail | 2017 |
| Iman Technical Services Ltd | Information & communication | 2018 |
| Imana Life Ltd | Hospitality | 2024 |
| Imay Rock Ltd | Real estate | 2024 |
| Imayam Ltd | Health & social care | 2024 |
| Imbue Consulting Ltd | Information & communication | 2001 |
| Imbuzi Limited | Health & social care | 2018 |
| IMC Investments Limited | Real estate | 2018 |
| Imcura Global Ltd | Professional & scientific | 2024 |
| IMD Consulting Ltd | Administrative & support | 2015 |
| Imdad UK Ltd | Hospitality | 2018 |
| Imedia Crafts Limited | Administrative & support | 2009 |
| IMH Conveyance Limited | Transport & logistics | 2026 |
| IMH Investments Limited | Real estate | 2019 |
| Imispharma Limited | Health & social care | 2025 |
| IMJ Ventures Limited | Other services | 2020 |
| Imlv Limited | Wholesale & retail | 2024 |
| IMM Investments Ltd | Real estate | 2023 |
| Immaculate Beauty Ltd | Other services | 2016 |
| Immaculate Ltd | Professional & scientific | 2004 |
| Immaculate Solutions (Commercial) Ltd | Administrative & support | 2026 |
| Immaculate Solutions Ltd | Administrative & support | 2024 |
| Immass Limited | Health & social care | 2025 |
| Immature Limited | Information & communication | 2011 |
| Immediators Ltd | Financial services | 2024 |
| Immerse Media Group Ltd | Information & communication | 2018 |
| Immersive AV Limited | Information & communication | 2016 |
| Immersive Media Ltd | Information & communication | 2005 |
| Immersive Projections Ltd | Manufacturing | 2023 |
| Immigration UK Services Ltd. | Professional & scientific | 2018 |
| Imogen COX Legal Limited | Professional & scientific | 2021 |
| Imolt Ltd | Real estate | 2003 |
| Impact Air Systems Limited | Professional & scientific | 1989 |
| Impact Combat Limited | Arts & recreation | 2016 |
| Impact Contracts Limited | Professional & scientific | 1996 |
| Impact Creative Group Limited | Other services | 2015 |
| Impact Design Advisory Limited | Professional & scientific | 2022 |
| Impact Foiling Group Limited | Financial services | 2020 |
| Impact Gardening & Property Maintenance Ltd | Administrative & support | 2025 |
| Impact Group (Leicester) Limited | Professional & scientific | 2008 |
| Impact Images Limited | Extraterritorial | 2009 |