Purpose: This study aims to examine the role of personal and subjective norms in predicting waste sorting, an increasingly relevant pro-environmental behavior. Design/methodology/approach: This study obtained data from a sample of 300 respondents from three Indonesian cities. Purposive sampling was employed to obtain information from specific segments of Indonesian population. The analysis consisted of a two-stage procedure including confirmatory factor analysis and covariance-based structural equation modeling. Findings: Results demonstrated that both subjective and personal norms significantly and directly predict waste sorting behavior (WSB) bypassing intention to behave. Research limitations/implications: The fact that norms held by individuals are able to single-handedly drive pro-environmental behaviors implies that previous studies and social marketing campaigns may have overstated the role of intention. Practical implications: In designing marketing communication programs promoting WSB, this paper argues that targeting normative tendencies of the audience may provide a more effective strategy than focusing on explicit pro-environmental intentions and attitudes of the public. Originality/value: This study provided a new experimental test and confirmation of the role of subjective norms, the normative component of the theory of planned behavior and of personal norms, the normative component of the norm activation theory, in predicting WSB. © 2021, Emerald Publishing Limited.