To examine the relationship between geographic access to Board Certified Behavior Analysts (BCBAs) among children with autism spectrum disorder (ASD) and county sociodemographic factors and state policy, we integrated publicly available data from the U.S. Department of Education's Civil Rights Data Collection, Behavior Analyst Certification Board's certificant registry, and U.S. Census. The study sample included U.S. counties and county equivalents (e.g., parishes, independent cities) in 49 states and D.C. (N = 3040). Using GIS software, we assigned BCBAs to counties based on their residence, allocated children via school districts to counties, and generated per-capita children with ASD/BCBA ratios. We distributed counties into five categories based on these ratios: no BCBAs (reference), = 31, 21-30, 11-20, > 0-10. We used a generalized logit model to conduct analyses. Highly affluent and urban counties had the highest access to BCBAs with odds ratio estimates for affluence ranging from 2.26 to 5.26. County-level poverty was positively associated with access, yet this relationship was moderated by urbanicity. Race-ethnicity and healthcare insurance coverage were negatively related to access. Other variables were not significant. Targeting non-urban and less affluent counties for provider recruitment and maintenance could most improve access to BCBAs. In addition to strategies specific to BCBAs for improving geographic access, traditional strategies used for other healthcare providers could be useful.