Trust is generally recognised as a reciprocal process between two parties leading to mutually beneficial outcomes and is critical to the success of organisations. However, theoretical detail on trust reciprocity is sparse and the examination of both parties in a trust relationship is uncommon in empirical studies. Ignoring this relational context can lead to an incomplete understanding of the nature of interpersonal trust, including the reciprocal patterns of influence, trust change over time, and the impact of trust incongruence within a dyad. Drawing on social exchange theory and interdependence theory, this study carries out a longitudinal examination of 230 dyadic workplace relationships involving five waves of data. Structural equation modelling examines three key areas. First, the actor-partner interdependence model provides evidence for reciprocal influences between the two parties. These results highlight that the more relational aspects of trustworthiness (benevolence) reciprocally influence the more affective forms of trust (disclosure), and that the more cognitive forms of trust (reliance) reciprocally influence interpersonal helping. Second, latent growth modelling shows that trust (reliance) is relatively stable whereas trust (disclosure) shows more change over time. Third, moderation analysis demonstrates that the impact of dyadic trust incongruence is detrimental to dyadic helping behaviours only when reliance forms of trust are unbalanced. The results confirm that trust is fundamentally a reciprocal and dynamic phenomenon and highlight different patterns of influence for reliance and disclosure forms of trust within work relationships.