<p>Open data portals represent a singular service for public access to open data, including government data. Nominally, anyone can access and utilise such portals. However, portals tend to cater to professional classes of users with domain expertise. In contrast, the public may encounter obstacles and barriers when accessing such portals. There is an increasing need for data portals to cater to a diverse user base, including the public, NGOs, and citizen scientists. This paper investigates the public’s understanding of open data and its capability to harness open data portals. Participants from several European countries were requested to complete a short survey and then tasked to use a portal to find information. Results indicate a broadly positive view of open data and open data portals. While the usability of open data portals is good, there is potential for improvement. It is recommended that further measures to increase usability be undertaken and efforts be made to raise public awareness of the existence and potential of open data portals.</p>