IOT or IoT may refer to:
- British Indian Ocean Territory, ISO 3166-1 alpha-3 code
- Internet of things, connecting everyday objects to the internet
- Illuminates of Thanateros, an international magical organization
- Inductive output tube, a variety of vacuum tube
- Institute of Transportation, an agency in Taiwan
- Input-Output Transfer, instructions for the PDP-8
- Completed operations indicator, in Belgian railway signalling
- Interocular transfer, a visual perception phenomenon