["Journal of Clinical Psychology, EarlyView. ", "\nABSTRACT\n\nObjective\nSocial anxiety disorder (SAD) is one of the most common mental disorders, with the majority of those affected not receiving primary care or psychotherapy. Internet‐based treatments may be an alternative for individuals with SAD. We hypothesize that interpersonal characteristics differ between SAD patients in face‐to‐face (ftf) and online treatments, and that these factors predict treatment outcomes.\n\n\nMethods\nThe sample consisted of 539 patients with SAD from four different online treatment studies (N = 376) and one university outpatient clinic in Europe (N = 163) who received integrative CBT. Interpersonal problems were assessed at baseline and symptom severity at baseline and treatment termination.\n\n\nResults\nResults showed similar interpersonal patterns of being nonassertive and socially inhibited in both treatment groups at baseline, with patients in online treatment being more severely affected than those in ftf therapy. Interpersonal problems of communion were predictive of outcome in both treatments. Low communion reflects interpersonal coldness, distance, and difficulty forming close bonds, whereas high communion reflects excessive dependence, submissiveness, and overinvolvement with others. Patients with interpersonal problems of low communion benefited more from ftf therapy, while patients with interpersonal problems of high communion benefited more from online therapy.\n\n\nConclusion\nThese findings underscore the importance of considering interpersonal problems when planning and evaluating treatment for SAD. In the future, it may be possible to predict if a particular SAD patient benefits more from online versus ftf treatment from their baseline interpersonal problems and recommend the suitable treatment.\n"]