A growing body of research examines the impact of recent teacher evaluation systems; however, we have limited knowledge on how these systems influence teacher retention. This study uses a mixed-methods design to examine teacher retention patterns during the pilot year of an evaluation system in an urban school district in Texas. We used difference-in-differences analysis to examine the impact of the new system on school-level teacher turnover and administered a teacher survey (N = 1,301) to investigate individual and school-level factors influencing retention. This quantitative analysis was supplemented with interview data from two case study schools. Results suggest that, overall, the new evaluation system did not have a significant effect on teacher retention, but there was significant variation at the individual and school level. This study has important implications for policymakers developing new evaluation systems and researchers interested in evaluating their impact on retention.