Introduction: Disruptions in self-monitoring processes represent key cognitive factors associated with schizophrenia spectrum disorders. In the current study, we assessed the effects of age and cognitive effort on self-monitoring for speech in adolescence, as well as its associations with personality dimensions pertaining to schizotypy and impulsivity.Methods: 121 community adolescents undertook a self-monitoring task that assesses the capacity to discriminate between self-generated overt and silent speech, for items requiring different levels of cognitive effort. Self-report measures were used to assess trait dimensions of schizotypy and impulsivity.Results: Cognitive effort, but not age, contributed to the overall rate of self-monitoring errors. Contrary to clinical psychosis and high risk samples, increased cognitive effort in healthy adolescents led to more internalising than externalising self-monitoring errors. Higher scores on the interpersonal dimension of schizotypy were associated with increases in the total rate of self-monitoring errors. No associations were found between positive schizotypy and externalising self-monitoring misattributions. Finally, trait impulsivity dimensions were not associated with self-monitoring performance.Conclusions: The present findings suggest that self-monitoring confusions may be linked to trait-risk for psychosis in adolescence. Future studies can prospectively assess whether the association between negative schizotypal traits and self-monitoring represents a distal marker of psychosis vulnerability.