Improving the state of citizens’ health is an urgent priority in many low and middle income countries (LMICs), and health management information systems (HMIS) are widely seen as valuable tools for pursuing this priority. Yet, the potential of HMIS has been difficult to materialize in the LMIC context since routines and practices that work against effective use of HMIS are often deeply embedded in historical institutions and, consequently, are difficult to change. Using a longitudinal case study of HMIS in Kenya, we investigate the crucial role of identity work as a mechanism that links information technology (IT) affordances to institutions. In particular, our study revealed four types of identity work (disruptive, legitimizing, reinforcing, and transformative) that, through different affordances, led to distinct institutional consequences in terms of either maintaining or deinstitutionalizing existing dysfunctional HMIS-related routines and practices. We demonstrate the importance of context for theorizing the societal and development impact of IT and the role of IT materiality in influencing deinstitutionalization.