Objectives Prevalence rate of diabetes is high among migrants. Whether migrants are correctly addressed to a standard quality of care for diabetes and are properly followed up are the questions addressed by this retrospective cohort study. Methods Compliance to one or repeated Guideline Composite Indicator (GCI), a standard process indicator of care quality, was tested in migrants compared to non-migrant Italian residents with diabetes, living in Tuscany Region, Italy, in years 2011-2015. For those with no GCI, the analysis was repeated for the chance of being tested by at least one or more HbA1c measurements.Results GCI compliance, in a single or repeated manner over time, was significantly less likely by about 15-20% among migrants (n = 3992) compared to non-migrants (n = 130,874), even after fully matching both cohorts. For those with no GCI, being tested by HbA1c was still significantly less likely among migrants. Conclusions Being addressed to a standard quality of care is impaired among migrant patients with diabetes living in Tuscany compared to non-migrants. Migrants, moreover, have a significantly lower probability of adhering to guidelines or to be tested by HbA1c measurement over time.