PurposeThere is little empirical evidence on how blockchain affordances may encourage consumers to make sustainable choices. Thus, this paper examines how blockchain affordances affect consumers’ sustainable consumption.Design/methodology/approachWe focus on three blockchain affordances: transparency, traceability, and immutability in this paper. By integrating the affordance lens and theory of consumption values (TCV), we develop a research model wherein we posit that blockchain affordances influence several consumption values, which then affect consumers’ intention to purchase sustainable products. In the study, we designed a scenario and user interface for a novel blockchain-based app for sustainable consumption in the context of the fashion industry and surveyed 295 European consumers to examine the study’s research model. We then analyzed the collected data using the partial least squares technique.FindingsThe results show that blockchain affordances positively affect consumption values, including efficiency, social impression, trust, and sustainability information clarity. In turn, these values influence the consumers’ purchase intention of sustainable products. Additionally, our post hoc analysis shows that these consumption values fully mediate the effect of blockchain affordances on consumers’ purchase intention, where trust and sustainability information clarity is found to have a higher impact.Originality/valueEmpirical research studies focusing on understanding blockchain’s effect on sustainable consumption values have been limited in prior literature. This study, drawing on the affordance lens, proposes distinct blockchain affordances and empirically validates their impact on consumers’ sustainable purchase intention. By integrating TCV, it highlights the mediating mechanism that drives blockchain’s impact on consumers’ purchase intention. We empirically identify the values that mediate the effects of blockchain affordances on consumers’ purchase intention; further, we discuss implications for research and practice based on the study findings.