| Acronym | Definition |
|---|
| ITU | International Telecommunication Union |
| ITU | International Telecommunications Union |
| ITU | International Triathlon Union |
| ITU | Information Technology Unit |
| ITU | Image Transfer Unit (printing) |
| ITU | International Technological University (San Jose, CA) |
| ITU | Institute for Transuranium Elements (EU) |
| ITU | Instrumentation Table Unit |
| ITU | International Telegraph Union |
| ITU | Istanbul Teknik Universitesi (Istanbul Technical University) |
| ITU | International Typographical Union |
| ITU | Indoor Transmit Unit (satellite broadband) |
| ITU | Install-Time Update |
| ITU | International Toxic Units |
| ITU | Imposto Territorial Urbano (Brasilian excise tax) |
| ITU | Information Transport Utility |
| ITU | Institutional Technical Unit (Washington State Network Services) |
| ITU | International Technical University (California) |
| ITU | Input Terminal Unit |
| ITU | Intent to Use/Trademarks |
| ITU | Intensive Therapy/Treatment Unit (similar to ICU) |