Aims: Adult congenital heart disease (ACHD) patients are at increased risk of sudden cardiac death and out-of-hospital cardiac arrest (OHCA). Currently, insufficient data exist on outcome, causes and circumstances of OHCA of ACHD patients resuscitated for OHCA. We investigate these parameters in ACHD patients in comparison to OHCA in the general population. Methods and results: We identified ACHD patients with OHCA by linking data from a Dutch nationwide registry of ACHD patients (CONCOR, n = 15,727), and ARREST, a cohort of OHCA cases (n = 17,868). 62 ACHD patients with OHCA were identified. Ventricular septal defect (n = 11), bicuspid aortic valve (n = 10) and atrial septal defect (n = 8) were the most common diagnoses. We included OHCA cases from the general population as controls. ACHD patients were younger than controls (n = 11,624) at the time of OHCA (47 (SD ± 17) years vs. 66 (SD ± 15) years, respectively, p < 0.001), and more often had a shockable initial rhythm (67% vs 40%, respectively, p < 0.001). A cardiac cause of OHCA was identified in 76% of ACHD patients, with only 7% due to myocardial infarction or ischemia. Survival was better in ACHD patients than in controls (44% vs. 19%, p < 0.001), but this difference disappeared after correction for age, gender, witnessed arrest, bystander resuscitation, public location and shockable rhythm. Conclusions: OHCA in ACHD patients occurs at young age, is rarely caused by ischemia and occurs mainly in patients with simple congenital defects. Risk stratification efforts should therefore not be restricted to ACHD patients with severe congenital defects.