The sale and purchase of socially and environmentally responsible festival clothing is a way for both attendees and event organizers to engage in ethical consumption. While existing research examines hypothetical willingness to pay for ethical festival clothing, there has been no research done on actual purchase behaviour. This study examined if attendees at Mariposa Folk Festival in Ontario, Canada would pay a premium for ethical festival t-shirts, and examined variables that influenced their purchase decision. A natural field experiment recorded the purchase of 350 festival t-shirts, and from this sample 181 purchasers participated in a supplementary survey. Results revealed that attendees paid a premium for the ethical festival t-shirts, and that purchase decision was effected by the visibility of the ethical certification, cost, and promotion of the ethical festival t-shirts at the t-shirt emporium. These results provide insight into what consumers are actually willing to pay for ethical festival clothing and the motivations behind their purchase decisions.