|Peer- and self-ratings are common components of performance appraisals for many organizations, including companies relying on team-based work. Self- and peer-ratings may represent the best way to monitor performance in both co-located and virtual teams. However, biases may affect performance ratings in the form of perceiver tendencies (e.g., leniency) or relationship-specific effects. In the current study, I examined team members’ ratings of task performance (i.e., contribution to the team’s project) and contextual performance. These behaviors are relevant to effective team performance, regardless of the particular team or the specific task. Using the social relations model, I examined the extent to which perceiver and target tendencies as well as unique perceiver-target relationships contribute to performance ratings. I also examined several other indicators of the types of processes that underlie peer performance ratings (i.e., reciprocity, true halo, halo bias, and self-other agreement). The results of this study provide further insight into the factors influencing peer performance ratings and whether the contribution of these factors to performance ratings differs for co-located and virtual teams.