| Abbreviation | Definition |
|---|---|
| IAC | Irvine Apartment Community |
| IACC | Indian Alcoholism Commission of California |
| IACO | Illinois Association of County Officials |
| IAEEE | International Association of Energy, Environment and Economy |
| IAS | Indian Administrative Service |
| IAWTP | Ithaca Area Water Treatment Plant |
| IBAT | Indiana Brownfields Advisory Team |
| IBC | Iowa Board of Certification |
| IBLA | Interior Board of Land Appeals |
| IC | Indiana County |
| ICA | Independent Commissioning Agent |
| ICAMA | Interstate Compact Adoption and Medical Assistance |
| ICAR | Improved Cross Area Review |
| ICC | Illinois Commerce Commission |
| ICC | Inter County Connector |
| ICCG | Iowa Community Cultural Grants |
| ICCP | Idaho Child Care Program |
| ICCW | Interagency Committee for Change by Women (Montana) |
| ICES | Indiana Client Eligibility System |
| ICHA | Idaho Commission on Hispanic Affairs |