ObjectiveExisting studies have highlighted suboptimal diabetes management in residential aged care facilities (RACFs). However, understanding of diabetes management in Australian metropolitan RACFs has been limited. This retrospective cohort study aimed to explore the pharmacological management of diabetes in 25 RACFs in Sydney Australia and assess concordance with clinical practice guidelines (CPGs).MethodsData from 231 permanent RACF residents aged ≥65 years and over with type 2 diabetes mellitus over the period from 1 July 2016 to 31 December 2019 were used. Concordance was measured by assessing the medications and medical history data for each individual resident for concordance with evidence‐based CPGs. Multivariable logistic regression was used to estimate the effect of resident characteristics on concordance with CPGs.ResultsOf the 231 residents with diabetes, 87 (38%) were not taking any antidiabetic medication. Pharmacological management inconsistent with CPG recommendations was observed for 73 (32%) residents, with the most common reason for non‐concordance being the use of medications with significant adverse effects in older adults (47, 2%). Residents with hypertension or other heart diseases in addition to their diabetes had greater odds of their diabetes management being non‐concordant with CPGs (OR = 2.84 95% CI = 1.54, 5.3 and OR = 2.64, 95% CI = 1.07, 6.41, respectively).ConclusionsPharmacological diabetes management in metropolitan Australian RACFs is suboptimal, with a high prevalence of inconsistency with CPGs (32%) observed. Additionally, having hypertension or heart diseases significantly increased the possibility of non‐concordance among diabetic RACF residents. Further investigation into the underlying relationships with comorbidities is required to develop better strategies.