The European Union (EU) is a complex political system and citizens’ knowledge about the EU is limited (Karp, Banducci, Bowler 2003). Given that individuals are biased information processors (Lodge and Taber 2006), they face a challenging situation when they need to decide on their country’s membership in the EU in a referendum while the public discourse is rife with myths and misinformation. Despite a rich literature on the factors that explain Euroskepticism (Hobolt and De Vries 2016) and EU referendum voting behaviour (Hobolt 2009, Hobolt 2016), we know very little about the role of misperceptions for Euroskepticism. This paper sheds light on the prevalence of misperceptions and examines their role for citizens’ attitudes towards the EU. The study relies on a unique population based survey with data on a random sample of about 1000 British citizens that was conducted shortly before the Brexit referendum in 2016.