--- - |2 Abstract Scholars agree that trust primarily has two bases: trustworthiness—the extent to which a trustee is competent, honest, and has goodwill toward the trustor—and trust propensity—a stable trait reflecting the trustor's generalized belief that others can be trusted. Due to this trait characterization, the literature has largely reached a consensus that trust propensity is only an important base of trust in the earliest stage of a relationship—before information on trustworthiness has been gathered. Additionally, the trait conceptualization of trust propensity inhibits it from being modeled as an explanatory mechanism. Drawing on accessibility theory, a theory of trait activation, we argue that trust propensity has state‐like characteristics that are “activated” by the daily treatment an employee receives from coworkers. Our model highlights that the social context—predominantly ignored in prior trust research because of its lack of relevance to dyadic perceptions of trustworthiness—can have a substantial impact on dyadic trust. Across two multisource experience sampling methodology studies, we provide evidence that state trust propensity transmits the effects of citizenship and deviance received to trust in a focal coworker, whether that focal coworker is a source of that treatment or not. We also address how general levels of workplace unfairness—a between‐person construct—influence these dynamics. We discuss the theoretical and practical implications of these within‐person dynamics for fostering trust within organizations. - Personnel Psychology, Volume 71, Issue 3, Page 423-455, Autumn 2018.