The nationwide Dutch Pediatric and Adult Registry of Diabetes (DPARD) was established to gain insights into the quality of Dutch diabetes outpatient care, in order to improve patient care and health outcomes. The DPARD cohort is a dynamic population of Dutch children and adults treated for diabetes in a hospital outpatient clinic or independent diabetes care centres across the Netherlands. Data are extracted directly from electronic health records of participating healthcare centres since 2017. The dataset comprises 135 variables related to patient characteristics, diagnostic tests, treatments, and clinical outcomes including complications. In total, 113,451 children and adults across the Netherlands were included, of whom 40,514 were diagnosed with type 1 diabetes (T1D) and 41,998 were diagnosed with type 2 diabetes (T2D). Of all Dutch healthcare centres, 88% had registered and 70% were contributing data. The percentage of patients with unknown values varied up to a quarter of the patients for most variables. The Dutch national registry DPARD plays an important role in evaluating diabetes care. While current DPARD data offer valuable insights, further data enrichment will enable even more solid conclusions. This study describes the basis for future research using DPARD.