This research examined the psychological mechanisms underlying anti-elite attitudes, focusing on the roles of economic insecurity and perceived economic inequality. In a preregistered study using a large representative sample across nine European countries (Belgium, Denmark, France, Greece, Hungary, Netherlands, Poland, Spain, and the UK, N = 11,217), we investigated whether feelings of relative deprivation explain the association between perceived personal economic insecurity and two anti-elite attitudes (i.e., populist attitudes and distrust in institutions) and whether perceived societal economic inequality reinforces these effects. The results show that (i) the more individuals feel insecure about their economic situation, the more they report anti-elite attitudes, (ii) which is explained by a greater feeling of relative deprivation (between 43% and 59% of variance explained), (iii) and this relationship is stronger for individuals who perceive greater economic inequalities within their country. This research provides evidence that feelings of relative deprivation constitute an important psychological process underpinning anti-elite attitudes across diverse economic, cultural, and political contexts.