Immigrants are at elevated risk for not having their diabetes treatment appropriately intensified, likely resulting in poorly-controlled diabetes and increased morbidity and mortality. Immigrant status is a powerful sociodemographic cue, yet its influence on providers' diabetes treatment decisions remains unknown. The study objective was to determine the effect of patient immigrant status on provider decisions to (1) take no action, (2) add an oral hypoglycemic agent (OHA), (3) add/switch to insulin, or (4) refer the patient to an endocrinologist. Participants were 140 medical students/professionals ('providers'). Providers viewed profiles (videos+vignettes) for virtual patients different in immigrant status (born in Mexico or U.S.; other characteristics held constant). Analyses were completed at the group and individual levels. Group levels indicated providers were less likely to refer foreign-born patients to endocrinology than U.S.-born patients (p=0.03). No differences were detected for the other three treatment likelihood ratings. Individual results indicated that about half of provider decisions were influenced by patient immigrant status (i.e., Cohen's d≥0.50) across all four decisions. Effect size data show an almost even split between higher treatment ratings for foreign-born vs. U.S.-born patients for three decisions (take no action, add an OHA, add/switch to insulin), explaining why group-level differences for these ratings did not emerge. This study found that providers are less likely to refer foreign-born patients to endocrinology, potentially leading to therapeutic inertia. In addition, half of individual-level provider decisions were meaningfully influenced by patient immigrant status. However, traditional group-level analyses mask these important individual-level differences. These systematic differences in treatment based on non-relevant factors could lead to unintended adverse outcomes for the foreign-born population.