A substantial body of research indicates that a teacher's identity is an essential aspect of their professional practice. As this body of research grows, researchers have increasingly sought to investigate the nature of pre-service teacher identities. This paper reports on a study that examined identities in the context of a pre-service cohort's online discussion group. By examining the group, this study attempted to address a gap in research knowledge, as research to this date has been unable to investigate pre-service teacher identities in non-course-endorsed or instructor-occupied spaces. A thematic and quantitative analysis of online postings by and interviews with group members provided an insight into how identities performed and related to one another within the online discussion group. The findings indicate that one category of identities emerged from a commitment to the social expectations and values of the group, whilst another emerged out of a personal resistance towards the social norms of group participation and involvement. This study may be useful for teacher educators deliberating the use of online spaces to support pre-service teacher identity development.