The summer melt and academic mismatch literatures have focused largely on college-ready, low-income students. Yet, a broader population of students may also benefit from additional support in formulating and realizing their college plans. We investigate the impact of a unique high school-university partnership to support college-intending students to follow through on their college plans. Specifically, we facilitated a collaborative effort between the Albuquerque Public Schools (APS) and the University of New Mexico (UNM), and randomly assigned 1602 APS graduates admitted to UNM across three experimental conditions: (1) outreach from an APS-based counselor; (2) outreach from a UNM-based counselor; or (3) the control group. Among Hispanic males, who are underrepresented at UNM compared to their APS graduating class, summer outreach improved timely postsecondary matriculation, with suggestive evidence that college-based outreach may be particularly effective. This finding is consistent with the social-psychological literature showing that increasing students’ sense of belonging at college can improve enrollment outcomes.