The moderating impact of emotional intelligence on free cortisol responses to stress. The construct of trait emotional intelligence (trait EI) refers to the individual differences in the perception, processing, regulation and utilization of emotional information. Several studies have found that trait EI was a significant moderator of subjective responses (e.g., mood deterioration, emotional intensity, action tendencies, bodily sensations) to both natural and laboratory stressors. The present study aims at extending these findings by examining whether trait EI also moderates the biological (i.e., cortisol) response to stress. To this end, 56 participants were assigned to either a neutral or a stressful condition (public speech task) and psychological and cortisol reactivity were examined. Results revealed that higher trait EI scores were associated with significantly lower reactivity to stress at both psychological (i.e., mood deterioration) and biological (i.e., salivary cortisol) levels. Additional analyses revealed that trait EI had incremental validity to predict stress reactivity over and above social desirability, alexithymia and the five-factor model of personality.