III
- 1/3 (disambiguation)
- 3 (disambiguation)
- 3i
- Information International, Inc.
- Innovative Interfaces, Inc.
- Institute for Information Industry
- Insurance Information Institute
- Insurance Institute of India
- Intelligence and Information Institute
- Interactive Investor International
- Interstate Identification Index
- Number Three (disambiguation)
- The Third (disambiguation)
- Third (disambiguation)
- Third party (disambiguation)
- Third person (disambiguation)