Due to the fragmented organizational landscape characterizing public transport, it is important to study and explore how regional governance of public transport adapts to national institutional reforms. By employing the term ‘governance cultures’ to a comparative case study of regional public transport planning in Sweden, we contribute to theories of governance by cultural sensitization. Combining governance theory with cultural analysis, we apply a cultural perspective to understand the two cases. We conclude that public transport planning in the Stockholm region is defined by ‘negotiations’ between stakeholders, whereas in the Västra Götaland region it is characterized by a governance culture of ‘collaboration’. The evidence from our case studies emphasizes the importance of understanding local governance practices as situated in cultural contexts as well as of viewing governance cultures as an important factor affecting the purpose, degree and outcomes of collaboration in planning practices.