Nonprofit scholars have long considered stakeholder targeting communication (STC), an important mechanism of organizational accountability to meet stakeholders’ diverse interests and needs. However, research has yet to systematically examine the antecedents and outcomes of organizations’ STC to advance a more comprehensive understanding of how organizations manage accountability demands in the digital era. To address this gap, this study proposes a conceptual framework to explain how organizations’ STC on social media (SM) is shaped by STC via non-SM channels and their external communication capacity and the resulting STC outcomes in the SM domain. Survey data from 156 humanitarian relief and development organizations on four continents showed that using non-SM channels to engage various groups of stakeholders helped build organizations’ external communication capacity, which in turn helped improve their engagement in STC on SM. STC on SM further contributed to organizations’ success in information dissemination, community building, and action mobilization outcomes on SM.