Anti-corruption claims have been at the core of many mass mobilizations worldwide. However, the nexus between corruption and collective action is often overlooked. Bridging social movement and corruption studies, this article contends that believing in extensive corruption has a positive impact on non-electoral forms of participation. But this effect is uneven across the population and contingent upon the individual’s political interest and education. Using survey data from 34 countries, the analysis confirms that people prefer non-electoral mobilization when institutions are seemingly captured by vested interests. Moreover, perceiving endemic corruption is likely to breed indignation among lesser-educated and less politically interested citizens, who are keener to embrace anti-elitist arguments and ultimately engage in extra-institutional behaviour. These findings help refine theories of societal accountability, which generally assume that politically sophisticated citizens are the driving force in the fight against corruption.