Background and objectivesReducing social anxiety development among incoming college students may improve college adjustment and mental health outcomes. This study tested whether cognitive bias modification for interpretations (CBM-I) reduces social anxiety and increases adjustment during the transition to college, and whether changes in outcomes would be mediated by changes in interpretation biases. MethodsParticipants (N = 73) were randomly assigned to a 3-session weekly CBM-I condition or symptom tracking (ST) control condition. Multilevel models were used to estimate within-person trajectories from baseline to one week post-intervention and to test whether trajectories differed by condition. ResultsThose in the CBM-I condition (vs. ST) reported higher increases in social adjustment across time. There were not significant differences between conditions for changes in social anxiety, academic adjustment, and personal adjustment. CBM-I was indirectly linked to improvements in outcome variables via more adaptive interpretation biases. LimitationsCBM-I was administered in a laboratory setting, requiring more resources than some computerized interventions. ConclusionsData tentatively support CBM-I for first-year students to increase social adjustment. Further, mediation findings provide support for targeting interpretation biases to improve social anxiety and adjustment outcomes. Yet, CBM-I did not outperform ST in improving social anxiety symptoms or other areas of college adjustment, and effect sizes were small, suggesting that more work is needed to amplify the potential of CBM-I as a therapeutic tool.