Purpose <p>Intolerance of uncertainty (IU) has been suggested to be a vulnerability factor in the development and maintenance of anxiety disorders. One suggested mechanism is that people high in IU have inflated estimates of threat expectancy. However, evidence supporting this mechanism has been mixed. In this study, we aimed at further elucidating the relationship between IU and threat expectancy by overcoming some methodological limitations of previous studies.</p> Methods <p>For this purpose, 147 participants completed a task in which, through a Pavlovian phase, they first learned the predictive relationship between four stimuli (geometric shapes) and an aversive US (aversive images) that was administered either in 25% or 50% of the trials. Participants were asked to indicate their threat expectancies at various time points. This learning phase was followed by a Decision-making phase, in which participants had to choose between two stimuli: one of the shapes shown in the Pavlovian phase and a new shape that provided explicit information about the US likelihood in case of being chosen.</p> Results <p>We found inflated self-report expectancies, as well as a significant positive association between threat expectancy and trait anxiety (TA), but not IU. In contrast, the results from the Decision-making phase suggest well accurate threat expectancies. No significant associations were found for either IU or TA.</p> Conclusions <p>By and large, our results do not provide evidence in favour of an association between IU and subjective threat expectancy estimates. Potential explanations are discussed in relation to our results and those from previous studies.</p>