Cognitive therapy for social anxiety disorder (SAD) based on the Clark and Wells model emphasizes negative beliefs about the social self and self‐consciousness as central causal factors. However, Wells' metacognitive model proposes that metacognitive beliefs are central to pathology universally. The relative importance of cognitive and metacognitive beliefs in the treatment of SAD is therefore an important research question. This study examined change in negative cognitive and negative metacognitive beliefs as independent correlates of symptom improvement in 46 SAD patients undergoing evidence‐based treatments. Both types of beliefs decreased during treatment. However, change in metacognitive belief was the only consistent independent predictor across all outcomes and change in cognitive beliefs did not significantly predict outcomes when change in self‐consciousness was controlled. The implication of this finding is that metacognitive change might be more important than cognitive belief change in symptom outcome and recovery in SAD. Key Practitioner Message Cognitive and metacognitive beliefs decreased during treatment of SAD. Change in self‐consciousness predicted symptom improvement. Change in metacognition predicted symptom improvement over change in cognition. Change in metacognition was a more reliable predictor than change in cognition.