Large organizations often require employees to collaborate with others who may see the world differently. Yet, little is known about whether misalignment in personal values with managers or colleagues affects performance. Using survey and administrative data from a world-leading bank, we find that employees who don’t share their manager’s values perform worse, with a stronger effect in objective productivity measures than subjective evaluations. This result is not explained by diversity in demographics or misalignment with organizational values. The productivity loss going from the least to the most misaligned worker is nearly four times greater than the impact of having a manager of a different gender. Differences in values with teammates do not have similar performance consequences. We provide evidence consistent with a decline in both employee-led communication and morale when workers have values different from those of their managers. Our findings reveal the important but often-overlooked influence of diversity in personal values on organizational performance.