Transnational political interest is the sustained attention to politics in at least two polities. Why do some immigrant-origin citizens show high levels of political interest in both their host countries and their familial countries of origin, some none, and others favour one over the other? With the 2017 Immigrant German Election Study, we describe the diverse patterns of transnational political interest among Germans from Turkey and their children, one of the largest immigrant-origin communities. We explicitly focus on the effects of three dimensions of integration and reveal that social integration has, by far, the strongest association with mean political interest. In addition, all dimensions of integration tilt the focus of political interest in favour of German politics, effects that are mediated by the individual identification with Germany and Turkey. Integration thus seems to activate immigrant-origin citizens into politics in general but tilts their transnational political interest towards host country politics.