At many institutions of higher education, first-year seminars are meant to help students transition to college life and to provide them with resources and skills to develop socially and academically, supporting persistence (Jamelske, 2009; Janz, 2004). Since their inception, researchers have evaluated the effectiveness of these seminars and their ability to reduce first-to-second-year attrition (Barefoot et al., 1998; Berry, 2014). In this study, extant literature addressing the efficacy of semester-long first-year seminars for reducing attrition was reviewed using meta-analysis, extending the work of Permzadian and Credé (2016). The meta-analysis included 74 effect sizes from 37 institutions with a total sample size of 92,508 students. Moderators of interest included contact hours per week and quality of research design. The results suggest first-year seminars helped retain students, but when selection bias was controlled for, these gains were nullified. Implications for policy in higher education and suggestions for future research are also discussed.