Visiting the beach is a popular activity, but the risk of drowning is real. Drownings are preventable, and swimming between the patrol flags can save lives. The aim of this study is to understand the beliefs people hold in relation to this important water safety behaviour. Participants (N= 514; females = 58%) who were residents of/visitors to coastal areas in South-East Queensland, Australia, completed a theory of planned behaviour belief-based questionnaire. The survey was designed to measure behavioural, normative and control beliefs guiding beachgoers' intentions to swim between the patrol flags. Controlling for age, gender and swimming ability, four critical beliefs (along with self-reported swimming ability) were identified as independently predicting intention. Specifically, the benefits of feeling safe and the cost of feeling limited in choice of where to swim, the social approval from partners and the inhibitor belief about better waves being outside the flags predicted intentions to swim between the flags. This study provides an understanding of the beliefs underlying Australian beachgoers' intentions to swim between the patrol flags. Attention to these targeted beliefs may assist in promoting more regular performance of this beach safety behaviour, thereby combating the increasing rates of drownings and surf rescues.