Health care reform has changed the landscape for the nation's health safety net, and school-based health centers (SBHCs) remain an important part of this system. However, few large-scale studies have been conducted to assess their impact on access to care. This study investigated differences in access among a nationally representative sample of adolescent SBHC users. An analysis using multivariate logistic regression examined the association between student characteristics and access to care. We found no differences based on race/ethnicity or insurance status among adolescent SBHC users; however, we did observe significant differences with regard to unmet health needs. School nurses serve as invaluable frontline staff who can facilitate equitable access to care, provide high-quality primary care, coordinate care for students with community health services, and advocate for policy and funding support of SBHCs as a critical part of the safety net for underserved adolescents.