Using secondary survey data from a national representative sample of Italian adult residents (N = 5,863, age range = 18–74 years, 54% females), this study aimed to test linear and nonlinear associations between religiosity and attitudes toward immigrants (i.e., xenophobia and tolerance) and examine moderating mechanisms of sociodemographic variables (i.e., age, gender, education, birth country, parental birth country, and contact with immigrants). Psychological measures included religiosity, xenophobia, and tolerance toward immigrants. A restricted cubic spline regression model with 3 knots best fit the data to explain both xenophobia and tolerance outcomes. Analyses of interaction effects evidenced nonlinearity between religiosity with xenophobia and tolerance only among participants who had contact with immigrants. Higher antiimmigrant attitudes were observed at both extremes of religiosity. Results are discussed in light of the contact hypothesis.