Although diverse patterns of college enrollment have gained attention in recent years, few studies have looked at students who take courses at four-year and two-year colleges simultaneously. Using a propensity score matching approach to compare outcomes of four-year college students who earned up to 10 credits at two-year colleges, termed "supplemental enrollment," with four-year college students who did not supplementally enroll, we find that supplementally enrolled students had higher bachelor's degree attainment, and better employment outcomes. Subgroup results suggest that supplemental enrollment may improve STEM degree attainment outcomes, particularly for low-socioeconomic-status and female students.