Science festivals are designed to expand the public's interest in science, but we find that this genre of science communication appeals mainly to a select clientele.

As part of our ongoing evaluation to determine how such activities might be improved (E. Jensen and N. Buckley Public Underst. Sci. 23, 557–573; 2014 and E. Jensen J. Sci. Commun. 14, Y05; 2015), we found that attendees at UK science festivals are more highly educated and economically advantaged than most of the population. Attendees are also disproportionately pro-science, and tend to be highly engaged in a wide range of cultural events.

This pattern reinforces existing sociocultural divides by benefiting privileged groups. Given their large investment in science communication, we recommend that scientists, universities and governments demand higher standards of inclusivity and use evidence-based practices at science festivals.