Early childhood temperament predicts intolerance of uncertainty in adolescence

•Intolerance of uncertainty is a transdiagnostic correlate of psychopathology.•Early childhood risk factors for intolerance of uncertainty have not been explored.•Child temperament is an important risk factor for psychopathology.•High childhood negative emotionality predicts adolescent intolerance of uncertainty.•Low childhood positive emotionality predicts adolescent intolerance of uncertainty. Intolerance of uncertainty (IU) is the trait propensity to react negatively to uncertainty. To date, very few studies have explored early childhood predictors of IU. The current study identifies relations between child temperament assessed at age 3 (N = 559) and IU assessed at ages 12 (N = 432) and 15 (N = 415). Temperament was assessed through both laboratory observation (Laboratory Temperament Assessment Battery) and maternal report (Children’s Behavior Questionnaire). IU was assessed through both maternal rating and child self-report using the 12-item Intolerance of Uncertainty Scale for Children. Higher levels of temperamental negative emotionality/neuroticism and lower levels of temperamental positive emotionality/extraversion assessed at age 3 predicted higher levels of IU in early-mid adolescence. Unique relationships were found at the trait facet level, and differences were observed between informants. These findings suggest that certain early child temperament traits can serve as markers of risk for difficulty dealing with uncertainty later in life. Future research should explore whether this relationship translates to increased risk for psychopathology.