Introduction: Access to health care is affected by social determinants of health. The social vulnerability index encompasses multiple social determinants of health simultaneously and may therefore be associated with healthcare access. Methods: Cross-sectional data were used from the 2016‒2019 Behavioral Risk Factor Surveillance System, a nationally representative U.S. telephone-based survey of adults aged ≥18 years. State-level social vulnerability index was derived using county-level social vulnerability index estimates from the Centers for Disease Control and Prevention Agency for Toxic Substances and Disease Registry. Analyses were performed in October 2021. Social vulnerability index was ranked according to percentiles, which were divided into tertiles: Tertile 1 (0.10−0.32), Tertile 2 (0.33−0.53), and Tertile 3 (0.54−0.90). Results: In multivariable-adjusted models comparing U.S. states in Tertile 3 with those in Tertile 1 of social vulnerability index, there was a higher prevalence of absence of healthcare coverage (OR=1.39 [95% CI=1.22, 1.58]), absence of primary care provider (OR=1.34 [95% CI=1.22, 1.48]), >1-year duration since last routine checkup (OR=1.18 [95% CI=1.10, 1.27]), inability to see a doctor because of cost (OR=1.38 [95% CI=1.23, 1.54]), and the composite variable of any difficulty in accessing healthcare (OR=1.15 [95% CI=1.08, 1.22]). Conclusions: State-level social vulnerability is associated with several measures related to healthcare access. These results can help to identify targeted interventions to improve access to health care in U.S. states with high social vulnerability index burden.