Metropolitan decision-making in flexible policy networks based on voluntary cooperation is present in most industrialised countries and a widely debated topic in governance research. The research focus primarily lies on the ability of metropolitan governance networks to organise area-wide public service provision efficiently and effectively – as opposed to hierarchical, bureaucratic policy-making. However, the inherent lack of input-orientated democratic legitimacy in governance institutions has only recently come to the forefront of research. In the present article, the democratic deficit of metropolitan governance is investigated with respect to the role of the municipal councillors and their inclusion in such institutions. The objects of study are local councillors in Swiss metropolitan areas, where regional cooperation is traditionally organised in functional associations that correspond to the flexible, informal logic of governance networks. The impact of metropolitan governance on the councillors’ political influence and on their behavioural patterns is assessed on the basis of large-scale survey data and comprehensive multilevel analyses accounting for the multilevel system of Swiss federalism.