| Institute of Australian Geographers | Academic & Science |
| Interweb Animatronics Guild | Academic & Science |
| Inner Array Grid | Academic & Science |
| Intel Architecture Group | Academic & Science |
| International Auditing Guidelines | Accounts and Finance |
| Niagara Falls (ny) | Airport Code |
| Illinois Attorney General | Business |
| Industry Advisory Group | Business |
| Interdepartmental Accounting Group | Business |
| Intermedia Advertising Group | Business |
| Insurance Archeology Group | Business |
| Intl Consol Air | Business |
| Industrial Alliance Insurance and Financial Services, Incorporated | Business |
| Insurance Australia Group Ltd | Business |
| Investor Advisory Group | Business |
| Independent Artist Group | Community |
| International Association of Geomorphologists | Community |
| Indiana Association for the Gifted | Community |
| IAGON | Cryptocurrency |
| International Association of Geodesy | Earth Science |
| In Another Game | General |
| itial Advice and Guidance | General |
| I'm A Goner | General |
| I Am Gay | General |
| Imas Age Gender | General |
| Ian Anderson Gray | General |
| Institutional Assistance Grants | General |
| Immunity Associated GTPase | General |
| Integrity Auto Group | General |
| Industry At a Glance | General |
| Industries At a Glance | General |
| Information Advice And Guidance | General |
| Interactive Application Generator | General |
| The Independent Action Group | General |
| International Assistance Group | General |
| International Airlines Group | General |
| Integrated Access Gateway | General |
| Intelligent Application Gateway | General |
| Interest Action Gallery | General |
| Inter-Agency Agreement | Governmental |
| International Audio Group | International |
| Italian angels for growth | International |
| International Association of Geoanalysts | International |
| International Armored Group | International |
| Inside Asian Gaming | International |
| International Army of Gamers | International |
| I Am Guessing | Internet |
| It's All Good | Internet |
| Internal Audit Group (of BVA) | Medical |
| Niagara Falls, New York USA | Regional |
| Insurance Australia Group | Regional |
| Niagara Falls International Airport | Transport & Travel |
