Emerging perspectives in neuroscience indicate that the brain functions predictively, constantly anticipating sensory input based on past experience. According to these perspectives, prediction signals impact perception, guiding and constraining experience. In a series of six behavioral experiments, we show that predictions about facial expressions drive social perception, deeply influencing how others are evaluated: individuals are judged as more likable and trustworthy when their facial expressions are anticipated, even in the absence of any conscious changes in felt affect. Moreover, the effect of predictions on social judgments extends to both real-world situations where such judgments have particularly high consequence (i.e., evaluating presidential candidates for an upcoming election), as well as to more basic perceptual processes that may underlie judgment (i.e., facilitated visual processing of expected expressions). The implications of these findings, including relevance for cross-cultural interactions, social stereotypes and mental illness, are discussed.