Health psychology shows that responses to risk and threat depend on perceptions as much as objective factors. The present study focuses on the precursors of perceived threat of COVID‐19. We draw on political and social psychology and use the aversion amplification hypothesis to propose that subjective uncertainty and political trust should interactively impact perceived threat. We conducted a cross‐sectional survey amongst the general population of Scotland (N = 188) in the early period of the COVID‐19 pandemic in the UK. We hypothesised that high political trust should ameliorate the threat‐elevating impact of uncertainty, thereby reducing the perceived threat from a high to moderate level. This hypothesis was supported, even after accounting for demographic differences. The discussion addresses the implications of the interactive role of trust and uncertainty for strategies to manage public behaviour as the pandemic progresses.