This study provides new evidence on how historical patterns of household formation shape the present-day level of trust. We test two distinct features of historical family arrangements that might be harmful to trust towards out-groups: (a) family extendedness in terms of the number of household members, and (b) generational hierarchy and gender relations within the household. To conduct our study, we compiled a historical database that reflects family structure and socio-economic development, mostly in the 19th century. The analysis was performed on a sample of 94 historical subnational units within eight contemporary Western and Eastern European countries that participated in the Life in Transition Survey in 2010. We find that cohabitation of several generations within the historical family and power of older generations over the younger are detrimental for out-group trust today. By contrast, family extendedness per se was revealed to have no impact on trust.