This study explores the relationship between students’ social and academic integration, basic psychological needs and academic success. By linking the social and academic integration, which is primarily focused on students’ relationships with peers and staff, to their psychological needs, we examine if need support in daily interactions would predict student success in their first year of college. The participants in this survey study, 140 first-year undergraduates, are enrolled in different universities of applied sciences in The Netherlands. The results of path analysis showed that peer interaction (social integration) directly supports students’ need for relatedness as it establishes close social bonds with peers, while at the same time it indirectly, supports students’ formal interaction with the teacher improving their intellectual involvement in the classroom. Most relevant to academic integration is students’ formal interaction with the teacher, which is mediated through autonomy and competence needs and academic success. Though primary support for academic success can be linked to formal teacher interactions, the indirect support through formal peer interactions should not be overlooked. These findings, at the outset, confirm the importance of need-supportive teachers, but they also point out the importance of need support by peers, which is less emphasized by self-determination theory.