This study draws on dual-processing theory and post-materialism assumptions to uncover the role of attitudinal and Materialistic values in determining the degree to which consumers are willing to pay premium prices for sustainable tourism services. Findings from a large-scale survey of Swedish potential ecotourists reveal that, while attitude and environmental beliefs relate positively to willingness to pay premium (WTPP) for ecotourism, materialistic values exert a negative effect In line with the theory of affect heuristics, study results further suggest that by giving rise to the intensity of feelings toward the offering, ecotourism interest alters the interplay of affective and evaluative antecedents, so that greater interest amplifies the influence, of affective attitude and materialistic values on WTPP while simultaneously attenuating the effect of environmental beliefs.