Vaccination intentions are widely regarded as individual decision, resting upon individuals’ attitudes and beliefs about the disease and their own health. In this research, we provide evidence that group factors, and more precisely, social cohesion — a multidimensional concept that encompasses one’s sense of connectedness to, and interrelations within, a group — can help us understand COVID-19 vaccination intentions. Using a representative sample of 3026 Australians, we first found evidence for the multidimensional structure of social cohesion, as a concept that includes positive social relations, social identification, and trust in government. Second, social cohesion assessed early in the COVID-19 pandemic predicted greater vaccination intention and lower perceived risk of vaccination four months later, after controlling for a series of demographic (i.e., sex, age, income) and health-related factors (i.e., subjective health; perceived risk; having been diagnosed with COVID-19). These results suggest that investments in social cohesion could have substantial and unexpected downstream benefits.