T ype 1 diabetes is a common chronic disease of childhood with substantial morbidity and mortality. 1 Optimizing glycemic management is key to preventing complications. 2,3 There are known socioeconomic status (SES) disparities in diabetes management and outcomes. 4,5 For Canadians, financial barriers to medications continue to be an important adverse social determinant of health. 6 This is important because insulin is life sustaining for people with type 1 diabetes.Ontario residents (population 14.5 million) have publicly funded coverage for medically necessary services but not for prescription medications. On Jan. 1, 2018, the Ontario government introduced publicly funded pharmacare (Ontario Health Insurance Plan [OHIP]+), the first payer for drugs for Ontarians younger than 25 years.Before the introduction of OHIP+, only people older than 64 years and those eligible for social assistance had access to publicly funded medications; all others paid out of pocket, through private insurance or were supported, in part, by the Trillium Drug Program (a government program that provides drug coverage for out-of-pocket expenses that are more than 4% of household income). The OHIP+ program covered the cost of medications on the provincial formulary, with no deductible or copayment. Fifteen months after its introduction, the Ontario government changed OHIP+ to exclude those patients with private drug coverage. 7 Thus, Ontario provides a unique "natural experiment" to assess the impact of 15 months of publicly funded pharmacare.Competing interests: Rayzel Shulman has received speaker fees from Dexcom. No other competing interests were declared. This article has been peer reviewed.