| Inter University Center | Academic & Science |
| Inter University Council | Academic & Science |
| International University College | Academic & Science |
| Institutional University Cooperation | Academic & Science |
| International University of the Caribbean | Academic & Science |
| Inter University Centre | Academic & Science |
| Inter-University Center for Japanese Language Studies | Academic & Science |
| International University of Chabahar | Academic & Science |
| International Underwater Contractors | Business |
| Internationalization and Unicode Conference | Community |
| International Undergraduate Community | Community |
| Innisfail Underwater Club | Community |
| Intelligent and Ubiquitous Computing | Computing |
| Institute of United Computers | Computing |
| Intergalactic Utilities Commission | General |
| Idiopathic Ulcerative Colitis | General |
| Image Unlimited Communications | General |
| Identificateur Unique De Client | General |
| Interconnect User Charge | General |
| Interconnect Usage Charges | General |
| Iron Uptake Chelate | General |
| Indwelling Urinary Catheter | General |
| Information Unit for Conventions | General |
| Integrated Urgent Care | General |
| Identification User Code | General |
| Intermediate Unit Commander | General |
| Interactive Utility Communications | General |
| Imposto Unico de Circulacao | General |
| Insufficient Undercarriage Clearance | General |
| Ireland Underwater Council | Governmental |
| International Users Conference | International |
| International Urban Cooperation | International |
| Indwelling Urethral Catheter | Medical |
| Invasive Urothelial Cancer | Medical |
| IntraUterine Contraceptive | Medical |
| Independent User Center | Military and Defence |
| Interconnection Usage Charges | Technology |
| Interconnect Usage Charge | Telecommunication |
