Purpose– The purpose of this paper is to explore fast-fashion consumers’ post-purchase behaviours and examine relationships among fast-fashion purchase, disposing, hoarding, participation in recycling, and environmental attitudes.Design/methodology/approach– A survey questionnaire was developed and a total of 335 college students completed it in a classroom setting. Of the data collected, 274 students who purchased fast-fashions were used for this study. Descriptive statistics were used to summarize the data and Pearson correlations were conducted to examine relationships among the variables.Findings– Results of Pearson correlations indicated that fast-fashion purchase was positively related to disposing and hoarding, but negatively related to participation in recycling. Apparel hoarding was positively related to recycling, but no relationships were found between environmental attitudes and any of the following: fast-fashion purchase, disposing, hoarding, or participation in recycling.Practical implications– Fast-fashion suppliers should encourage consumers’ participation in recycling and should take responsibility for collecting their post-purchase products.Originality/value– This paper provides important contributions to the literature about fashion retailing/marketing and post-purchase behaviours. Although young fashion-oriented consumers easily purchase and dispose of trendy and cheap fast-fashions, little is known about their post-purchase behaviours. Findings of this study showed that fast-fashion consumers had positive attitudes towards the environment, yet they did not participate in recycling. The finding implies that fast-fashion suppliers need to develop a culture to support sustainability of consumption.