| Imago Ltd | Information & communication | 2026 |
| Imanifay Limited | Wholesale & retail | 2023 |
| Imari and Turquoise LLP | | 2019 |
| Imativ Ltd | Real estate | 2014 |
| Imce Ltd | Education | 2026 |
| Imense Ltd | Administrative & support | 2004 |
| Imhotex Limited | Professional & scientific | 2020 |
| IMI Europe Holdings Limited | Financial services | 2015 |
| Imims UK Ltd | Administrative & support | 2021 |
| Immaterial Ltd | Professional & scientific | 2015 |
| Immense Paradise Ltd | Wholesale & retail | 2025 |
| Immersive Publishing Ltd | Information & communication | 2020 |
| Immunotherapeutics Consultancy Ltd | Information & communication | 2019 |
| Immutrin Ltd | Professional & scientific | 2019 |
| Impact Crew Ltd | Professional & scientific | 2001 |
| Impact MAR & Comms Limited | Extraterritorial | 2020 |
| Impala Management Company Limited | Households | 2000 |
| Impala Medico Ltd | Administrative & support | 2020 |
| Imperfect Impact Limited | Wholesale & retail | 2024 |
| Imperial Estate Development Ltd | Construction | 2022 |
| Imperial Estate Holding Ltd | Real estate | 2022 |
| Imperial Estate Investment Ltd | Real estate | 2022 |
| Imperior Ltd | Administrative & support | 2023 |
| Impirial Build Ltd | Transport & logistics | 2017 |
| Implant Analysis Limited | Health & social care | 2016 |
| Implied Logic Limited | Information & communication | 2010 |
| Impulse PR Ltd | Financial services | 2021 |
| Imran Group Limited | Manufacturing | 2024 |
| Imsquared Ltd | Professional & scientific | 2023 |
| Imvoto Limited | Education | 2012 |
| Imzi Holdings Limited | Financial services | 2026 |
| IN Residence Dining Ltd | Hospitality | 2026 |
| IN Service Compliance Limited | Professional & scientific | 2023 |
| IN the Swim Group Limited | Information & communication | 2021 |
| IN Vita Ltd | Information & communication | 2022 |
| In-Flight Cabin Solutions Ltd | Manufacturing | 2009 |
| IN2MINDS Limited | Administrative & support | 2008 |
| IN2R Pharma Ltd | Health & social care | 2025 |
| Inaer Ltd | Manufacturing | 2024 |
| Inamuk Limited | Hospitality | 2025 |
| Inaya Consultancy PVT Ltd | Administrative & support | 2024 |
| Inayah Birth Ltd | Health & social care | 2025 |
| Inbility Ltd. | Wholesale & retail | 2016 |
| Inbox Leads Limited | Other services | 2022 |
| Inca Digital Printers Limited | Manufacturing | 2000 |
| Incatuk & Mbsu Ltd | Construction | 2026 |
| Incatuk Limited | Agriculture & fishing | 2017 |
| Ince Building Management Limited | Construction | 2025 |
| Incha Cambridge Ltd | Wholesale & retail | 2021 |
| Inchi Trust Limited | Information & communication | 2009 |
| Incisive Development Limited | Extraterritorial | 2007 |
| Inclume Ltd | Professional & scientific | 2018 |
| Inclusion Training Ltd | Education | 2025 |
| Inclusive Parties CIC | Health & social care | 2023 |
| Inclusive Sportswear CIC | Education | 2023 |
| Increaworks UK Ltd | Wholesale & retail | 2023 |
| IND2WORLD Ltd | Wholesale & retail | 2024 |
| Indefinite Articles | Arts & recreation | 2000 |
| Indegra Therapeutics Limited | Professional & scientific | 2022 |
| Independence Educational Publishers Limited | Information & communication | 2002 |
| Independent Optics Group Ltd | Financial services | 2023 |
| Independent Optics Holdco Ltd | Financial services | 2023 |
| Independent Thinkers Education Limited | Education | 2015 |
| Independent Veterinary Specialists Limited | Professional & scientific | 2016 |
| Index for Inclusion Network | Education | 2013 |
| Index Instruments Limited | Manufacturing | 2025 |
| Indian Ocean Cambs Ltd | Hospitality | 2018 |
| Indian Palace Cambridge Limited | Hospitality | 2020 |
| Indian Palace Restaurant Limited | Hospitality | 2018 |
| Indian Spice Littleport Ltd | Hospitality | 2019 |
| Indian Vegetarian Norfolk Ltd | Hospitality | 2019 |
| Indigo (INT) Ltd | Information & communication | 2025 |
| Indigo Business Solutions Limited | Information & communication | 2003 |
| Indigo Project Resources Ltd | Information & communication | 2014 |
| Individual Pubs Limited | Hospitality | 2001 |
| Industrial Design Associates Ltd | Other services | 2020 |
| Industrial Imagineering Ltd | Information & communication | 2019 |
| Industrial Inkjet Ltd | Manufacturing | 2005 |
| Industrial Site Services (Cambridge) Limited | Manufacturing | 2008 |
| Induventional Consulting & Services Co Ltd | Wholesale & retail | 2017 |
| Inea UK Limited | Professional & scientific | 2017 |
| Inferenc Limited | Professional & scientific | 2014 |
| Infersol Ltd | Information & communication | 2025 |
| Infi International Limited | Extraterritorial | 2019 |
| Infinet Technologies Ltd | Wholesale & retail | 2006 |
| Infinite Advantage Group Limited | Professional & scientific | 2015 |
| Infinite Electronics U.K. Holdco Limited | Manufacturing | 2022 |
| Infinite Sustainable Property Limited | Real estate | 2025 |
| Infinite Ventures Group Limited | Financial services | 2025 |
| Infinitex Education Ltd | Education | 2020 |
| Infiniti Recycling Ltd | Professional & scientific | 2023 |
| Infinity Hotel Supplies UK Limited | Extraterritorial | 2020 |
| Infinity Ignite Ltd | Wholesale & retail | 2025 |
| Infinity Island Studio Limited | Information & communication | 2023 |
| Infinity Mechanical Services & Medical Gasses Ltd | Construction | 2025 |
| Infinity Portals Limited | Other services | 2016 |
| Infisynth Tech Ltd | Information & communication | 2024 |
| Inflatable Records Limited | Information & communication | 2011 |
| Infonomica Limited | Real estate | 2000 |
| Infopoint Ltd | Information & communication | 2000 |