Activity in the sympathetic branch of the autonomic nervous system tends tocovary amongst romantic partners. Studies of interpersonal physiology suggest that romantic partners possess the ability to influence each other’s physiological states, which may be observable through systematic covariation in partners’ physiological activity (i.e., physiological synchrony). However, very few studies have directly tested physiological synchrony across conversation contexts, which is a notable gap in the literature given that social context may modulate the implications of physiological synchrony on relational functioning. Using electrodermal skin conductance as a measure of autonomic activity, this study used multilevel vector autoregressive modeling to test for time-lagged physiological synchrony across different-gender romantic partners while they discuss 1) a mutual stress and 2) a topic of mutual enjoyment. Strong carryover (i.e., autoregressive) effects were observed in both female and male partners in both conversations. Unidirectional time-lagged synchrony was observed in the mutual stress conversation, with female skin conductance preceding and predicting male skin conductance, on average. No time-lagged synchrony effects were observed in the enjoyment conversation, on average. Across both conversations, physiological synchrony varied greatly between each couple. Findings prompt future studies to further explore physiological synchrony using multiple physiological indicators to identity couple-specific dynamics.