Tourism-related industries have emphasized the wellness tourism market when numerous countriesnow face an aging population. Many studies have indicated that strong customer service increases com-petitive advantage. However, customer service-related research from the perspectives of customers andoperators is rare. This study adopted a two-phase approach to incorporate the perspectives of older adultsand operators in wellness tourism into the service factors. We extracted service factors from face-to-faceinterviews with senior managers and experienced consultants of the hot springs hotel industry con-ducted in Phase 1. During Phase 2, we interviewed older adults at hot springs, and performed exploratoryand confirmatory factor analyses to examine the reliability and validity of customer service factors. Theresults highlighted the following seven customer service factors: “health promotion treatments,” “mentallearning,” “experience of unique tourism resources,” “complementary therapies,” “relaxation,” “healthydiet,” and “social activities.” According to these service factors, the older adults interviewed were dividedinto a holistic group, physiocare group, and leisure and recreation group using cluster analysis. Finally,we propose socio-demographic variables for describing the specific characteristics of the three clustersidentified