Trust is the social glue that holds society together. The academic consensus is that trust is weaker among lower-class individuals and in unequal regions/countries, which is often considered a threat to a healthy society. However, existing studies are inconsistent and have two limitations: (i) variability in the measurement of social class and (ii) small numbers of higher level units (regions/countries). We addressed these problems using large-scale (cross-)national representative surveys (encompassing 560,000+ participants from 1,500+ regional/national units). Multilevel analysis led to two consistent sets of findings. First, the effects of social class on social trust were systematically positive, whereas the effects on institutional trust depended on the way social class was measured. Second, the effects of income inequality on social and institutional trust were systematically nonsignificant and smaller than the smallest negative effect of interest. Our findings suggest that researchers need to update their knowledge: social class—not income inequality—predicts trust.

信任是使社会团结在一起的社会粘合剂。学术上的共识是，在下层阶级之间以及在不平等的地区/国家之间，信任度较弱，这通常被视为对健康社会的威胁。但是，现有的研究并不一致，并且有两个局限性：（i）社会阶层的衡量方法的可变性；（ii）少数高层单位（地区/国家）。我们使用大规模（跨）国家代表调查（包括来自1,500多个区域/国家/地区的560,000多个参与者）解决了这些问题。多级分析得出了两组一致的发现。首先，社会阶级对社会信任的影响是系统地积极的，而对制度信任的影响则取决于社会阶级的衡量方式。第二，并小于所需的最小负面影响。我们的发现表明研究人员需要更新他们的知识：社会阶层而不是收入不平等可以预测信任。