As e-commerce sales grow, the number of product returns becomes an increasing burden on companies and the environment. Reducing the number of returns would have benefits for both the online retailer, in terms of cost reduction and competitiveness, and the environment, in terms of improving the sustainability of e-commerce. In this article, we compare gamification approaches with and without green nudging. Both approaches aim to motivate customers’ shopping behavior in order to reduce the return rate. In our study, we analyze whether green nudging overpowers the effect of gamification elements. We present the results of two survey-based online experiments (n = 973 and n = 1010) on gamification with and without green nudging (GwN and GoN). Following the self-determination theory, we examine the influence of GwN and GoN on autonomy, competence, and relatedness need satisfaction, as well as the return and purchase motivation of the survey respondents. Using regression, structural equation, and moderation analyses, we find that green nudging is so powerful in the context studied that it overshadows most gamification effects, at least in the short run. Moreover, both approaches appear to be effective but also have potential negative side effects on purchase motivation.