Political trust has long been seen as fundamental for societal cooperation and democratic legitimacy. However, evidence about its consequences are partial and fragmented, and we do not currently have a systematic understanding of whether political trust warrants such vast attention. This paper conducts a systematic review and meta-analysis of 61 studies reporting 329 coefficients derived from over three and a half million observations globally. After synthesising the theoretical frameworks in the extant literature, the meta-analysis results show that trust is weakly to moderately related to outcomes as diverse as voter turnout, vote choice, policy preferences and compliance, but is unrelated to informal participation. These results are robust to a range of design considerations such as measurement of trust, modelling strategy, and region of study. By systematically analysing the extant research, the paper provides a robust, systematic and empirical foundation to advance research on political trust.