BACKGROUND: Analysis of multi-institutional data and benchmarking is an accepted accreditation standard in cardiac surgery. Such a database does not exist for congenital cardiac surgery in Australia and New Zealand (ANZ). To fill this gap, the ANZ Congenital Outcomes Registry for Surgery (ANZCORS) was established in 2017. METHODS: Inclusion criteria included all cardiothoracic and extracorporeal membrane oxygenation (ECMO) procedures performed at five participating centres. Data was collected by data managers, validated by the surgical team, and securely transmitted to a central repository. RESULTS: Between 2015 and 2019, 9723 procedures were performed in 7003 patients. Cardiopulmonary bypass was utilized for 59% and 9% were ECMO procedures. Fifty-seven percent (n = 5531) of the procedures were performed in children younger than 1 year of age. Twenty-four percent of procedures (n = 2365) were performed in neonates (≤28 days) and 33% (n = 3166) were performed in children aged 29 days to 1 year (infants). The 30-day mortality for cardiac cases (n = 6572) was 1.3% and there was no statistical difference between the participating centres (P = 0.491). Sixty-nine percent of cases had no major post-operative complications (5121/7456). For cardiopulmonary bypass procedures (n = 5774), median stay in intensive care and hospital was 2 days (IQR 1, 4) and 9 days (IQR 5, 18), respectively. CONCLUSION: ANZCORS has facilitated pooled data analysis for paediatric cardiac surgery across ANZ for the first time. Overall mortality was low. Non-risk-adjusted 30-day mortality for individual procedures was similar in all units. The continued evaluation of surgical outcomes through ANZCORS will drive quality assessment in paediatric cardiac surgery across ANZ.