A growing literature examines local approaches to migration using concepts of sanctuary and solidarity cities. Recently, studies have broadened their focus to include comparative analyses and expanded both the contextual and geographical scope. We respond to this trend by examining different ways in which migrant rights initiatives relate to urban scales. First, we review literatures on local migration politics, which tend to emphasise either exclusive or inclusive aspects. We propose to bridge the focus on local migration regimes and on solidarity cities. Second, we present results of a frame analysis highlighting that migrant rights initiatives operate in an ambivalent and fragmented field. Nevertheless, the frames also cling to positive notions of a local community and neighbourhood so that neither a one-sided view of the city as a community of solidarity nor as a mere regime of control does justice to the radical imaginaries and prefigurative politics enacted at urban scales.