| Institute for Doctoral Studies in the Visual Arts | Portland, ME | Graduate school | Private nonprofit |
| Institute of American Indian and Alaska Native Culture and Arts Development | Santa Fe, NM | University | Public |
| Institute of Buddhist Studies | Berkeley, CA | Graduate school | Private nonprofit |
| Institute of Lutheran Theology | Brookings, SD | University | Private nonprofit |
| Institute of Taoist Education and Acupuncture | Louisville, CO | Graduate school | Private nonprofit |
| Institute of World Politics | Washington, DC | Graduate school | Private nonprofit |
| Instituto Tecnologico de Puerto Rico-Recinto de Guayama | Guayama, PR | College | Public |
| Instituto Tecnologico de Puerto Rico-Recinto de Manati | Manati, PR | College | Public |
| Instituto Tecnologico de Puerto Rico-Recinto de San Juan | San Juan, PR | College | Public |
| Inter American University of Puerto Rico-Aguadilla | Aguadilla, PR | University | Private nonprofit |
| Inter American University of Puerto Rico-Arecibo | Arecibo, PR | University | Private nonprofit |
| Inter American University of Puerto Rico-Barranquitas | Barranquitas, PR | University | Private nonprofit |
| Inter American University of Puerto Rico-Bayamon | Bayamon, PR | University | Private nonprofit |
| Inter American University of Puerto Rico-Central Office | San Juan, PR | University | Private nonprofit |
| Inter American University of Puerto Rico-Fajardo | Fajardo, PR | University | Private nonprofit |
| Inter American University of Puerto Rico-Guayama | Guayama, PR | University | Private nonprofit |
| Inter American University of Puerto Rico-Metro | San Juan, PR | University | Private nonprofit |
| Inter American University of Puerto Rico-Ponce | Mercedita, PR | University | Private nonprofit |
| Inter American University of Puerto Rico-San German | San German, PR | University | Private nonprofit |
| Inter American University of Puerto Rico-School of Law | San Juan, PR | Graduate school | Private nonprofit |
| Inter American University of Puerto Rico-School of Optometry | Bayamon, PR | Graduate school | Private nonprofit |
| Interdenominational Theological Center | Atlanta, GA | Graduate school | Private nonprofit |
| International Baptist College and Seminary | Chandler, AZ | University | Private nonprofit |
| International Institute for Restorative Practices | Bethlehem, PA | Graduate school | Private nonprofit |
| Inver Hills Community College | Inver Grove Heights, MN | College | Public |