As demand for college graduates grows (Times Higher Education, 2023) persistence rates for first-generation students continue to lag (Toutkoushain et al., 2018, 2021). Complicating our understanding of this opportunity gap is the diversity of how first-generation student status is defined (Jo Peralta & Klonowski, 2017). We argue that while notable differences exist between first-generation students whose parents have no college experience (FGS-none), and those from families with collegiate backgrounds (continuing-generation), the distinctions between first-generation students with parents who have some college experience (FGS-some), and the other two groups are unclear. As such, this study investigates the implications of varying definitions of first-generation college student status through the lens of student social capital and retention. Using a comprehensive survey and data analysis, the study reveals no significant differences in students' cumulative social capital. However, examining social capital through principal component analysis revealed disparities in family social capital (FGS-none and FGS-some) and peer social capital (FGS-none). Further, lower levels of cumulative social capital and family social capital were significantly related to lower retention. The findings underscore the importance of academic support tailored to first-generation students, particularly FGS-none, and incorporating strategies within curriculum aimed at bolstering the social capital of first-generation students, especially during their critical freshman year. We argue that while postsecondary institutions should continue to use a broad definition of first-generation student status to catch the most at-risk students, research should continue to collect and explore the nuances between first-generation student populations and the role of social capital in student success.