Recent advances in social psychological research have shown that national integration policies influence how immigrants are perceived and treated by the mainstream population. However, the processes by which these policies come to have an impact on prejudice and well‐being of the general population are largely unknown. Moreover, past research has often relied on unrepresentative samples limiting generalizability. The present research proposes that when the national integration policies of a given society are perceived as clearly defined and coherent, they have a direct impact on the perceived cultural norm related to those national integration policies. In turn, the perceived cultural norm affects personal attitudes toward cultural norms (i.e., the degree to which individuals support a given policy), which influence the level of anti‐immigrant prejudice as well as psychological well‐being. Findings from two correlational studies with representative samples of the mainstream population conducted in France on the policy of secularism (N = 940) and in Québec on the policy of interculturalism (N = 912) supported the proposed theoretical model.