| IACT | Imaging Atmospheric Cherenkov Telescope 
| Others |
| IACT | Indian American Coalition of Texas
| Others |
| IACT | Indiana Association of Cities and Towns
| Others |
| IACT | Integrated Air Charge Temperature
| Others |
| IACT | International Academy of Computer Technology
| Others |
| IACT | International Academy of Computer Training
| Others |
| IACT | International Alliance for Compatible Technology
| Others |
| IACT | International Association of Counselors and Therapists
| Others |