Past research on capital structure was spearheaded by the ground-breaking models of Nobel Prize laureates Modigliani and Miller. However, little research has been done on the application of their and other theories to banking institutions in South Africa. The study analyses the determinants of the capital structure of banks in South Africa based on secondary financial data and by performing this analysis attempts to establish trends in capital structure policy and regulatory compliance. The study also identifies best practices that contribute to the overall performance of the banking institution. Conclusions drawn from the results and literature create greater understanding of the dynamics of capital structure and its implications for South African banks.