This randomized controlled trial examined the impact of The Connection Project, an experiential, relationship‐focused intervention designed to improve school belongingness and decrease symptoms of depression and loneliness among new college students. Participants were 438 first‐year and transfer students (232 treatment, 206 waitlist‐control) at a medium‐sized, 4years, predominantly White public university in the Southeastern United States. At postintervention, the treatment group reported significant relative increases in school belonging and significant relative reductions in levels of loneliness and depressive symptoms in comparison to waitlist‐controls. Program effects were stronger for students from marginalized racial or ethnic backgrounds, students from lower socioeconomic status households, and transfer students. Results are interpreted as suggesting the utility of experiential, peer‐support prevention programming to promote college students' well‐being, particularly college students who hold identities that are traditionally disadvantaged in this context.