AbstractObjectiveThis study explored the associations among relational uncertainty, relational turbulence, dyadic synchrony, and cohabitation status among newlyweds.BackgroundMarriage is a highly desired institution across racial groups, gender identities, sexual orientations, and socioeconomic status. However, divorce rates remain high and marital problems early in the relationship are more predictive of dissolution.MethodsWe developed a preliminary instrument to test dyadic synchrony, an outcome variable within relational turbulence theory (RTT). EFA results suggested a two‐factor measure of dyadic synchrony: conversational comfort and ease and communication coordination and authenticity. We used structural equation modeling (SEM) to investigate direct and indirect theoretical associations among relational uncertainty, relational turbulence, and dyadic synchrony. An online survey was administered to a sample of newlyweds (N = 234) through Amazon's MTurk.ResultsResults indicated that relational uncertainty and turbulence, predicted dyadic synchrony; turbulence also mediated these associations. Finally, results indicated no differences between premarital and marital cohabiters' experiences of relational uncertainty, turbulence, and dyadic synchrony.ConclusionThe study results offer theoretical and methodological insights as well as translational implications for newlyweds, family systems, and clinicians.ImplicationsIf couples and their support systems view relational uncertainty and turbulence as a likelihood, this could help normalize their experiences and remove feelings of worry, shame, and guilt. Moreover, clinicians working with partners in premarital counseling or couples therapy could incorporate these findings into treatment such that partners could better adjust expectations, build awareness, and develop conflict resolution and strong communication skills.