AbstractThe fashion industry has not fully addressed the movement towards sustainability head‐on. The purpose of this study was to identify factors influencing environmentally friendly apparel purchase intentions using the theory of planned behaviour as a guide. In this case, environmental knowledge, environmental concern and attitudes towards environmentally friendly apparel purchase behaviour make up the attitude component. In addition to social pressure, we suggest environmental guilt also makes up the dimension of normative influence. Furthermore, the study extends the theory of planned behaviour's idea of perceived behavioural control beyond previous behaviour and convenience, also taking into account willingness to pay. Data were collected from 220 American adults via an online consumer panel. The results show that individual environmental attitudes, environmental concern and knowledge, social pressure to behave in an environmentally friendly manner, environmental guilt, perceived environmental impact, past environmentally friendly apparel purchases, accessibility and cost of environmentally friendly apparel all impact purchase intentions. Furthermore, previous purchases, attitudes towards purchasing environmentally friendly apparel and social pressure are the strongest indicators of future environmentally friendly purchase behaviour. Managerial implications are discussed.