Stress impacts cognitive and emotional processing by effecting chemical changes throughout the brain, including cortisol levels. The impact of this change may differ based on task type—due to region-specific variations in glucocorticoid receptor densities—and the acute or chronic nature of the stressor. The Stroop task is a well-established means of assessing interference from irrelevant information. Chronic stress and exogenous cortisol administration may increase Stroop interference; however, less is known about how acute stress and endogenous cortisol increase affects Stroop performance, and whether this differs for emotional and cognitive distractors. The present study included 64 participants who experienced a high or low stress manipulation before completing a computerized colour- and emotion word Stroop task. Manipulation checks confirmed that participants in the high stress group experienced significantly more physiological (cortisol, heart rate, blood pressure) and subjective stress than those in the low stress group. The high stress group demonstrated less emotion word interference for accuracy than the low stress group. Correlational analyses also showed that greater increases in subjective stress were associated with less emotion word interference for accuracy overall and less colour word interference for accuracy in the high stress group, and greater increases in cortisol were associated with less colour word interference for reaction time in the low stress group only. While past research suggests that chronic stress or exogenous cortisol administration are associated with greater interference, the results of the present study suggest that acute stress may facilitate accuracy and reaction time on tasks requiring inhibition of irrelevant cognitive and emotional information.