Data on the incidence and risk factors of sudden cardiac death in patients with bipolar disorder are lacking in the literature. By using data from the Taiwan National Health Insurance Research Database and Department of Health Death Certification System between 2000 and 2016, we conducted a prospective national cohort study to determine the incidence and risk factors of sudden cardiac death in bipolar disorder patients. The study cohort included 46,490 patients with bipolar disorder, 467 of whom experienced sudden cardiac death. Stratified analyses showed that the standardized mortality ratios (SMRs) of sudden cardiac death were all above 1.00 across each age interval, with the highest SMR in patients aged <30 years (31.96, 95% CI: 20.47-47.55). Notably, hypertension raised the risk of sudden cardiac death in both patients aged <50 years (1.85, 95% CI: 1.23-2.79) and aged ≥50 years (1.44, 95% CI: 1.14-1.83). In addition, venous and lymphatic disorders (1.97, 95% CI: 1.23-3.16), and alcohol use-related disorder (2.34, 95% CI: 1.62-3.38) elevated the risk of sudden cardiac death in patients aged <50 years. Congestive heart failure (1.59, 95% CI: 1.13-2.23) and dementia (1.75, 95% CI: 1.30-2.35) increased the risk of sudden cardiac death in patients aged ≥50 years. The risk of sudden cardiac death is remarkably high in bipolar disorder patients across the lifespan. Prevention strategies specific to individuals with bipolar disorder are urgently required.