Social presence (SP) positively influences online students' motivation, satisfaction, retention, and learning outcomes. Although crucial for successful online learning experiences, little work has examined the evolution of SP over time or the effect of peer-interaction on SP. Using a longitudinal social network analysis approach (i.e., stochastic actor-oriented model), we investigated how SP perceptions evolved over a cohort of three consecutive courses. Students were asked to nominate peers with whom they share affectively in the course and to report their SP perceptions. The results suggest that over time learners reciprocate nominations, and those who nominated more peers reported higher levels of SP. Although there was no evidence of imitation, the “rich-get-richer-effect” was observed as SP perceptions decreased. Our study contributes to the definition of SP as a perception rather than an ability and reaffirms SP course design as essential at the beginning of an online learning experience.