Introduction-In 2014, the Affordable Care Act (ACA) provided funding for states to expand Medicaid coverage to include citizens who earned up to 138% of the federal poverty line. We sought to ascertain whether physicians practicing in Medicaid expansion states reported an increase in Medicaid or newly insured patients with type 2 diabetes in their panels, compared to physicians practicing in non-expansion states. Methods-We conducted a 55-question cross-sectional survey of 356 physicians providing outpatient care for adults with type 2 diabetes. We used adjusted multivariate logistic regression analyses to compare responses from physicians who practiced in expansion vs. non-expansion states regarding whether they observed an increase since 2014 in 1) the number of Medicaid or newly insured patients with diabetes and 2) the number of additional newly or previously diagnosed patients who were newly receiving care, in their panels, adjusting for physician, practice, and patient-level characteristics, weighted for the U.S. physician population. Results-41% of eligible recipients responded. 64.2% of physicians who practice in an expansion state report an increase in Medicaid or newly insured patients with diabetes compared with 46.1% who practice in non-expansion states (p = 0.05; Table 2). Conclusion-Compared with physicians who practice in non-expansion states, physicians who practice in Medicaid expansion states are more likely to report an increase in the number of Medicaid or newly insured patients with diabetes in their practice since 2014. The increased