Emerging adulthood is a period when religious beliefs are likely to be shaped. Studying the influence of religious culture on prosocial behavior among emerging adults aids our understanding of the process and effects of religious socialization. Mormon religious culture places a particularly strong emphasis on caring for family and fellow Mormons. Because intrinsically religious individuals internalize their religious community's values, we hypothesized that the relationship between intrinsic religiosity and volunteering would be stronger among Mormons than among Catholics or non‐Catholic Christians. We tested this hypothesis using a sample of Mormon (N = 118), Catholic (N = 304), and non‐Catholic Christian (N = 542) emerging adults (18–29 year olds) across three volunteering contexts (religious, family, and secular). Controlling for extrinsic religiosity and worship attendance, the relationship between intrinsic religiosity and frequency of volunteering was greater among Mormons than Catholics and non‐Catholic Christians in the context of religious and family volunteering. However, intrinsic religiosity was not a significant predictor of secular volunteering. Our findings suggest that Mormon culture influences the frequency and type of volunteering engaged in by young Mormon adults.