Adolescence is characterized as a developmental period of risky decision-making. During this developmental window there is also a marked increase in actual and perceived stress. Acute stress increases risky decision-making in adults, but no research has examined this phenomenon in adolescents. In this study, an ecologically relevant approach was used to document daily self-reports of stress in adolescents and an emerging adult comparison group. Participants visited the laboratory twice: once each when they endorsed a high and low level of stress, where they performed a risky decision-making task and a response inhibition task. In both groups, participants showed greater risky decision-making under high (vs. low) stress conditions but no stress-related effects on response inhibition. The dissociation between decision-making and response inhibition under stress suggests that, across development, individuals show greater vulnerability to contextual influence in decision-making domains.