IOA may refer to:
Locations Islands of Adventure, a Universal Destinations & Experiences theme park in Orlando, Florida Institute of Astronomy, Cambridge UCL Institute of Archaeology Ioannina National Airport, an airport serving the Greek town of Ioannina
Organizations Indian Olympic Association Independent Olympic Athletes International Olympic Academy Institute of Acoustics, Chinese Academy of Sciences Institute of Acoustics (United Kingdom), a British engineering society International Ombudsman Association International Oversight Advisory, a fictional organization in the Stargate franchise Irish Orienteering Association
Other Input Output Application, a method used to add communicate websites and software, inputting and outputting data. Input-output analysis, an economics model Information object address, IEC 60870-5-104