Research has demonstrated that social support is crucial in mitigating stress and enhancing mood. Not only do long-term, meaningful relationships contribute to well-being, but everyday social interactions, such as small talk, also offer psychological benefits. As social robots increasingly become more integrated into daily life, they present a potential avenue for stress interventions. In our online study, 98 participants underwent a stress induction using the Stroop task and were then assigned to one of three conditions: engaging in scripted small talk with a simulated NAO robot online, listening to a neutral story told by the same NAO robot, or no intervention (control condition). Results indicate that both interventions effectively reduced stress, with a tendency towards a stronger effect in the Small talk condition. Small talk not only helped maintain positive affect but also reduced negative affect. Notably, the benefits were more pronounced among individuals experiencing higher acute stress following the stress induction, but were less evident in those with chronically elevated stress levels. Furthermore, the effect of the intervention on stress reduction was mediated by changes in positive affect. These findings suggest that small talk with a social robot may serve as a promising tool for stress reduction and affect regulation.