Emotions dynamically unfold and are jointly constructed throughout social interactions between individuals. Yet, how exactly the experience and expression of emotions interact throughout such interactions remains poorly understood. In this study, we investigated the interplay between the experience and verbal expression of negative affect within and between romantic partners during negative interactions. We examined this interplay in terms of four possible relations: (a) how one's experienced negative affect predicts the verbal expression thereof, (b) how the verbal expression of negative affect predicts a subsequent change in one's own experienced affect, (c) how the verbal expression of negative affect predicts change in a partner's experienced affect, and (d) how one's experienced negative affect predicts the verbal expression of negative affect by a partner. We answered these questions by analyzing second-to-second data of self-reported affect ratings and verbatim transcripts of videotaped negative interactions between romantic partners. Our findings reveal inconsistent evidence for intraindividual relationships between the experience and verbal expression of negative affect. Yet, they demonstrate a consistent, though small, interpersonal relation with the expression of negative affect in one partner predicting the subsequent experience of negative affect in the other. These results suggest that verbal negative emotion expression may be more consistently related to others' experience than one's own, and highlight the role of emotion expression in interpersonal emotion regulation and the social construction of emotional experience, though the small effect sizes suggest this relationship may be subtle and that many other factors contribute to our emotional experiences. (PsycInfo Database Record (c) 2025 APA, all rights reserved).