This paper proposes a process model for habit formation in IS post-adoption. On the basis of extant literature (in IS and other fields), we provide insights into five important constructs that play a role in the formation of IS-use habits: satisfaction, reinforcement, frequency, extent of use, and stability in context. Our proposed model is dynamic in nature and highlights the relative roles of habit and intention as antecedents of IS post-adoption use. The proposed model was developed in three phases. Phase I explains the initial interaction of users with the system, which may pave the way to habit formation. Phase II sheds light on the actual development of habits and highlights the balance between habits and intention as antecedents of IS use. Phase III provides insights on how a habit can crystallize. The paper closes with a discussion of implications for researchers and practitioners.