| Individualized Honors Program | Academic & Science |
| Integrated Humanities Program | Academic & Science |
| IHOP Corporation ( International House Of Pancakes) | Business |
| Institut Henri Poincar | Business |
| IHP (formerly Industrial Heating and Plumbing) Industrial, Inc. | Business |
| Intellego Hlgds | Business |
| International Hydrological Program | Earth Science |
| Help File (watcom) | File Type |
| Internet Highway Patrol | General |
| Indiana Highway Patrol | General |
| Iowa Highway Patrol | General |
| Iraqi Highway Patrol | General |
| Interstate Highway Patrol | General |
| Inner Helmholtz Plane | General |
| International Hydrological Programme | General |
| International Humanitarian Partnership | General |
| Imperial Hobby Productions | General |
| Innovative Hearth Products | General |
| Individuals and Households Program | General |
| Irregular Hunter Productions | General |
| International House Philadelphia | General |
| International Honors Program | General |
| Illinois Home Performance | General |
| Integral Horse Power | General |
| Idaho Highway Patrol | General |
| Illinois Highway Patrol | General |
| Institute of Human Performance | Governmental |
| Institute for Human Performance | Governmental |
| International Hospitality Program | International |
| International Honors Programs | International |
| Independent Husbandry Panel (tuberculosis control in cattle in the UK) | Medical |
| Intravenous Hydrogen Peroxide | Medical |
| Ingham Health Plan | Medical |
| Integrated Health Plan | Medical |
| International Health Policies | Medical |
| Individualized Healthcare Plans | Medical |
| Integrated Health Partnerships | Medical |
| Integrated Health Project | Medical |
| Innovative Health Plan | Medical |
| Interfaith Health Program | Medical |
| Institute of Health Professions | Medical |
| Individual Hotel Promotion | Messaging |
| Individual Human Performance | Military and Defence |
| Indicated Horsepower | Space Science |
