--- - |2 Abstract Among the various forms of transnational grandparenting is the engagement of the so‐called zero generation – the transnationally mobile parents of adult migrants – in caring for their grandchildren abroad. It constitutes a distinct kind of intergenerational solidarity within transnational families. By taking migrant families in Switzerland as a case in point, in this article we attempt to broaden the existing research by adopting a comparative, qualitative approach towards understanding the commonalities and differences of childcare organization involving grandparental support in European and non‐European transnational families. By taking into account the main objective and the temporality of grandparents' visits in Switzerland, we identify six different types of childcare arrangements. While these arrangements are shaped by the discriminatory Swiss migration regime, several other institutional, familial, and individual factors help to promote or impede them, or to change their dynamics. Thus, we introduce an innovative, multi‐level, analytical approach towards studying the various ways in which the parents of adult migrants of different nationalities take part in the transnational circulation of care. - 'Global Networks, EarlyView. '