| Indigenous Research Center of the Americas | Academic & Science |
| Illinois Roof Consulting Associates | Business |
| International Register Of Certificated Auditors | Business |
| Instant Reach Client Advertising | Business |
| Indiv Rest Assd | Business |
| Indiana Roofing Contractors Association | Business |
| Iowa Roofing Contractors Association | Business |
| International Ragdoll Cats Association | Business |
| International Railway Congress Association | Business |
| Illinois Recreational Cheerleading Association | Community |
| Institut Royal de la Culture Amazighe | Community |
| International Rural Churches Association | Community |
| Interkingdom Rules Committee For Amtgard | Community |
| International Real Combat Association | Community |
| International Radio Club of America | Community |
| Iowa Rodeo Cowboys Association | Community |
| International Ragdoll Cat Association | Community |
| Indian Railway Conference Association | Community |
| Interest Rate Cap Agreement | General |
| Industrial Revenue Collection Area | General |
| Integration Repository Creation Assistance | General |
| IL Recreational Cheerleading Assoc | General |
| Information Reform and Control Act | Governmental |
| Immigration Reform And Control Act | Governmental |
| International Register of Certificated Auditor | International |
| International Railways of Central America | International |
| International Risk Control Academy | International |
| International Reupholstery Corporation of America | International |
| International Register of Civil Aircraft | International |
| Indiana Resource Center for Autism | Medical |
| International Register of Certified Auditors | Medical |
| Indigenous Remote Communications Association | Regional |
