The Asia-Pacific region shows potential for growth in the spa market, particularly in Thailand. However, the contrast between the growing day spa industry and the industry’s lack of knowledge about day spa users highlights the importance of understanding spa-goers’ preferences and considerations with regard to spa selection. Studies of consumers’ decision making regarding spa choice commonly cite product quality, therapist quality, ambience quality and price as important determinants. This study used a choice experiment to examine consumers’ decisions about day spas via a simulation in which trade-offs were inevitable. The findings suggested that therapist quality was the most dominant attribute in determining spa-goers’ choices, followed by product quality, ambience quality, and price. Good therapist and treatment quality led respondents to select spas, whereas poor therapist and treatment quality led them to reject spas. Good ambience quality did not significantly affect spa choice; however, poor ambience quality led to spa rejection. The findings of this study are discussed together with implication for spa managers. The results of this study have important implications for the spa industry in terms of understanding the key drivers of choice among spa customers.