Volunteering in civil society organizations (CSOs) is sometimes idealized as welcoming arena for everybody. Prior research, however, has shown that participation in volunteer work depends on gender, wealth, education, and social networks, suggesting that CSOs are not in fact open to everyone. Inequality within different fields of volunteering combined with the factors that put actors into more powerful positions has rarely been scrutinized. Besides identifying the characteristics and resources relevant for promotion, we primarily investigate how these patterns differ between four subfields: politics, social services, religion, and sports. We analyzed a large database created from the Austrian micro-census. The findings reveal significant relations between the actors’ gender, their occupational and educational status, and their hierarchical positions in CSOs within each of the subfields. Our results indicate that the extent to which social inequality spills over to volunteering depends on field characteristics: In the fields of sports and politics, occupational status plays a major role, while in the fields of religion and social services, educational status is more important. We explain these differences through organizational and individual factors that characterize these social fields.