The second year of college is a time when students remain at increased risk of departure. Compared to widely available first-year resources, institutional support for second-year students is more limited. The purpose of this study was to compare second-to-third year retention between students who participated in a comprehensive second-year experience program (SEP; n = 2,622) with students who did not participate (n = 4,823). Because students' participation in SEP was optional, we used propensity score matching to account for potential selection bias. Students who participated in SEP were retained at higher rates than students who did not participate, even when accounting for potential selection bias. Retention differences were especially notable among participants and nonparticipants from systemically minoritized backgrounds. These findings extend prior research that meaningful involvement in high-impact practices supports second-year students' retention. We conclude with implications for leaders responsible for second-year programing on their campus.