Previous research on the antecedents of people’s judgments of procedural and interactional fairness has focused primarily on situational factors. Across three studies we find that dispositional tendencies, in particular people’s general propensity to trust others, also influence fairness perceptions. People who were more trusting had more positive perceptions of procedural and interactional fairness, even when they were exposed to identical fairness information. We also found that dispositional trust in particular predicted fairness perceptions whereas other individual difference variables reflecting general positivity did not. Moreover, in all three studies, perceptions of fairness mediated the positive relationship between dispositional trust and work attitudes (e.g., organizational commitment), suggesting that one reason people who are more trusting exhibit more positive work attitudes is because they are more likely to believe they are treated fairly. Implications for the justice and trust literatures are discussed.