Using the Belief Action Outcome (BAO) framework as a theoretical basis, this study investigates the mechanisms that link organizational beliefs about environmental sustainability with Green information system (IS) actions that are undertaken and, hence, the organizational benefits accruing from these actions. Survey data were collected from 156 small and medium-sized enterprises (SMEs) and analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM). The results support the notion that Green IS endeavors lead to increased organizational benefits. External pressures from stakeholders and employees’ attitudes to environmental sustainability affect the organizational attitude to Green IS. The attitude to Green IS is further translated into the organization’s strategy and corresponding Green IS actions, resulting in organizational benefits. This study’s main contribution lies in establishing a link between personal attitudes, institutional mechanisms, internal environmental/sustainability initiatives, and performance implications. Green IS adoption was empirically validated considering the SME context.