| Abbreviation | Definition |
|---|---|
| IHCA | Iowa Health Care Association |
| IHOA | Illinois Health Occupations Association |
| IHOA | Indianapolis Hockey Officials Association |
| IHRA | International Harm Reduction Association |
| IHRA | International Hot Rod Association |
| IHSA | Intercollegiate Horse Shows Association |
| IHSAN | International Hadith Study Association Network |
| IHSSA | Idaho High School Swimming Association |
| IIAA | Islamabad Industrial Area Association |
| IIAC | Investment Industry Association of Canada |
| IIAL | Islamic Insurance Association of London |
| IICA | International Ice Cream Association |
| IIEA | International Intelligence Ethics Association |
| IIEA | International Iranian Economic Association |
| IIFA | Illinois Intercollegiate Forensics Association |
| IIFA | Inazawa International Friendship Association |
| IIFA | International Investment Funds Association |
| IIFA | Irish International Freight Association |
| IIOA | Indiana Industrial Operators Association |
| IIOA | International Input Output Association |