The convenience of shopping online has changed the way consumers buy pieces of clothing - getting fast deliveries of multiple items in various colors and sizes and returning the ones they dislike. Unfortunately, this comes with a rise in shipping volumes, in terms of both last mile (LM) and returns, which ultimately carries negative externalities on the environment. Thus, the purpose of this paper is to analyze the environmental impact of fashion e-commerce LM deliveries and returns, identify improvement opportunities and derive initial recommendations for greener practices. Conducting a cross-case analysis on six retailers, we conclude that the environmental impact from LM deliveries and returns deserves a higher priority for it is rapidly growing. While large firms execute numerous green initiatives and involve their logistics service providers, their increasingly high return rates create large negative impacts on the environment. Smaller companies, on the other hand, demonstrate little initiative and interest in investing efforts to improve their environmental impact even though these may result in higher economic returns.