| Iddiols Ashphalt Limited | Construction | 2023 |
| IDE Apps Ltd | Information & communication | 2026 |
| Ideal Espresso Limited | Hospitality | 2016 |
| Ideal Heat Solutions Limited | Administrative & support | 2010 |
| Idealhome Property Ltd | Transport & logistics | 2022 |
| Iden Park Ltd | Real estate | 2023 |
| Iden Properties Ltd | Real estate | 2018 |
| Identify Online Limited | Real estate | 2015 |
| Identispec Limited | Professional & scientific | 1999 |
| IDF Investments Limited | Real estate | 2019 |
| Idivision Limited | Information & communication | 2010 |
| IDL Trans Ltd | Transport & logistics | 2017 |
| Ieyenet Ltd | Health & social care | 2022 |
| Igbuild Homes Limited | Construction | 2025 |
| Ignite Pilates Ltd | Arts & recreation | 2026 |
| Ignivara Limited | Information & communication | 2026 |
| Ihistroy Limited | Construction | 2025 |
| IHT1973 Consulting Limited | Professional & scientific | 2021 |
| Iiandc Limited | Transport & logistics | 2025 |
| IJD Roofing & Building Limited | Construction | 2014 |
| Ijeomajude Ltd | Wholesale & retail | 2025 |
| IJS Educational Services Ltd | Education | 2023 |
| IK Transport Ltd | Transport & logistics | 2015 |
| Ikerson Ltd | Wholesale & retail | 2020 |
| Ikshana Limited | Financial services | 2024 |
| Ilbaga Ltd | Transport & logistics | 2018 |
| ILE Scents Ltd | Wholesale & retail | 2023 |
| Ilex Beauty Limited | Other services | 2022 |
| Ilex Industries Group UK Ltd | Construction | 2022 |
| Ilford and Dagenham Properties Limited | Real estate | 1936 |
| Ilis Properties Ltd | Real estate | 2020 |
| Illimited Ltd | Construction | 2026 |
| Illumino Ignis (Kent) Limited | Administrative & support | 2019 |
| Image Ideas Limited | Wholesale & retail | 2008 |
| Image Tint Limited | Wholesale & retail | 2015 |
| Image Works Media Ltd | Administrative & support | 2006 |
| Images (Hollingbourne) Limited | Professional & scientific | 2015 |
| Imagink Limited | Administrative & support | 2009 |
| Imana Ltd | Hospitality | 2019 |
| IMD Surgery Limited | Public administration | 2021 |
| IME Equestrian Events Limited | Arts & recreation | 2023 |
| IME Liveries Limited | Education | 2024 |
| IME Loan Horses and Ponies Ltd | Education | 2022 |
| Immillmoon Limited | Information & communication | 2025 |
| Imoc-Uk Ltd | Other services | 2007 |
| IMP Health International Ltd | Health & social care | 2016 |
| Impact Connect Media Ltd | Information & communication | 2024 |
| Impact Home Improvements Ltd | Construction | 2018 |
| Impact Industries Limited | Arts & recreation | 2019 |
| Impact Pathways Solutions Ltd | Construction | 2026 |
| Impact Returns Ltd | Professional & scientific | 2026 |
| Impala Pinaize Company Limited | Administrative & support | 1977 |
| Imperial'Z Limited | Other services | 2025 |
| IMPETUS9 Ltd | Professional & scientific | 2019 |
| Imprint Design & Media Limited | Professional & scientific | 2022 |
| IN Good Order Ltd | Financial services | 2023 |
| In-Space UK Limited | Administrative & support | 2006 |
| Inc Courier Ltd | Transport & logistics | 2018 |
| Incalesco Ltd | Wholesale & retail | 2024 |
| Ince Building Ltd | Construction | 2022 |
| Inclusive Futures Alliance CIC | Other services | 2025 |
| Incredipebble Ltd | Administrative & support | 2015 |
| Independent Codependency Ltd | Professional & scientific | 2025 |
| Independent Telecom Brokers Limited | Information & communication | 2002 |
| India Village Maidstone Limited | Hospitality | 2024 |
| Indian Heaven Ltd | Hospitality | 2022 |
| Indian Masala Ltd | Hospitality | 2021 |
| Indian Summer Car Sales Ltd | Wholesale & retail | 2007 |
| Indiego Photography Ltd | Information & communication | 2008 |
| Indigo Edition Ltd | Professional & scientific | 2025 |
| Indisium Properties Ltd | Real estate | 2021 |
| Indmedics Limited | Health & social care | 2013 |
| Indus Gold Limited | Professional & scientific | 2011 |
| Industrial Barbers UK Ltd | Other services | 2025 |
| Industrial Refrigeration Solutions Limited | Construction | 2010 |
| Industrial Services Solutions Limited | Professional & scientific | 2017 |
| Infa & BI Solutions Limited | Information & communication | 2014 |
| Infersens Limited | Professional & scientific | 2017 |
| Infinite Alchemy Ltd | Water & waste | 2022 |
| Infiniti Venture LAB Ltd | Professional & scientific | 2025 |
| Infinity Fencing Ltd | Manufacturing | 2018 |
| Infinity Group South East Limited | Construction | 2026 |
| Infinity Plus Care Services Ltd | Health & social care | 2023 |
| Influential (Holdings) Limited | Financial services | 2015 |
| Influential Software Services Limited | Administrative & support | 1993 |
| Infocom UK Ltd | Manufacturing | 2020 |
| Infocus Accountancy Services Limited | Professional & scientific | 2012 |
| Infocus Finance Solutions Limited | Professional & scientific | 2013 |
| Infosoft Solutions Ltd | Information & communication | 2024 |
| Infrastructure Kent Ltd | Construction | 2025 |
| Ingalash & Co Ltd | Other services | 2023 |
| Ingenium Property Solutions Ltd | Real estate | 2017 |
| Ingeniumz Technology Limited | Information & communication | 2022 |
| Ingleside Design Company Limited | Construction | 1999 |
| Inhouse Property Hub Ltd | Hospitality | 2021 |
| Inhouse SA Services Ltd | Real estate | 2023 |
| Inicio CK Limited | Health & social care | 2024 |
| Initiate Project Solutions Limited | Professional & scientific | 2013 |
| Injection Development (Canterbury) Limited | Wholesale & retail | 2006 |
| Injury Therapy Pro Limited | Health & social care | 2016 |