Following Stakeholders' Theory, stakeholders' positive behavioural change towards green banking is essential for banks to adopt green banking. Employing Behavioural Response Theory (BRT), we examined retail bank customers' intention to adopt green banking in New Zealand using 254 online survey responses. We examine whether retail bank customers' environmental knowledge moderates the association between attitude towards green banking and intention to adopt green banking. We find retail bank customers prefer green banking although some of them do not yet intend to adopt green banking. The findings confirm that environmental knowledge has a weak negative moderating effect on the association between attitude towards green banking and intention to adopt green banking. The responses from this study indicate there are specific factors that affect and limit retail bank customers' intentions to adopt green banking.