This research analyses medical tourists' perceptions of Thailand's medical tourism service quality. A content analysis of international patients' online testimonials from the Tourism Authority of Thailand's official medical tourism website shows that medical tourists have distinct perceptions of Thailand's medical tourism service quality, with the SERVQUAL dimensions assurance and reliability being mentioned most frequently. Service quality perceptions varied depending on patients' home country region, type of medical treatment received, if healthcare provider personnel were referred to in the testimonials, and whether Thailand was recommended as a medical tourism destination. Marketing communication implications of the results are discussed, including using assurance and reliability as risk-reducing cues, and future research ideas are submitted.