Politics and Business magazines
- IDEXX Laboratories, Inc.
- IDG Books Worldwide, Inc.
- IdraPrince, Inc.
- IDT Corporation
- IDX Systems Corporation
- IEC Electronics Corp.
- Igloo Products Corp.
- IHC Caland N.V.
- Ihr Platz GmbH + Company KG
- IHS Inc.
- II Fornaio (America) Corporation
- II-VI Incorporated
- IKEA International A/S
- IKON Office Solutions, Inc.
- Illinois Bell Telephone Company
- Illinois Central Corporation
- Illinois Power Company
- Illycaffè SpA
- ILX Resorts Incorporated
- Imagine Foods, Inc.