In research on teacher induction, scholars have pointed at the pivotal role of collegial support to overcome the challenges inherent to the first years of teaching. In this quantitative study, we extend current work by using a social network perspective to examine characteristics (i.e. network size, frequency and perceived usefulness) of professional, emotional, and social collegial support networks. Moreover, we explore the extent to which these characteristics explain key factors affecting teacher retention, namely job satisfaction, intrinsic motivation to teach, and self-efficacy. An online survey was completed by 292 beginning primary school teachers in Flanders (Belgium). Social network data showed that, on average, they receive professional, emotional and social support from six colleagues each week and found this mostly useful. Regression analyses demonstrated that network size and perceived usefulness of professional, emotional, and social collegial support networks were positively related to job satisfaction and intrinsic motivation to teach, thus confirming the importance of collegial support in teacher induction. Frequency of support was not significant. Finally, no substantial relationship was found between collegial support and teachers' self-efficacy. Implications of these findings for practice and policy are discussed.