Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): Karolinska Institue at Stockholm South hospital. Background In atrial fibrillation (AF), anti-arrhythmic drugs are an option for rhythm control. Guidelines regarding treatment with sotalol varies worldwide. The risk of serious adverse events in AF patients on sotalol is estimated from small studies, with short follow-up, not designed for mortality analysis. Purpose To evaluate mortality in patients with a rhythm control strategy for AF. Methods In Swedish registries, 7473 sotalol-treated and 107255 patients on betablockers underwent cardioversion or were diagnosed with paroxysmal AF between 2006 and 2017. Mortality and ventricular arrhythmias were estimated in unadjusted, and propensity score matched cohorts. Results Mean follow up was 474 (SD 599) and 481 (SD 515) days in sotalol/betablocker respectively. Crude all-cause mortality was lower in the sotalol group (HR 0.3 CI 0.3-0.4), also in multi-adjusted analysis (HR 0.6 CI 0.5-0.6). In the propensity-matched comparison, HR remained lower on sotalol (0.6 CI 0.5-0.7). Ventricular arrhythmias were more common among patients on sotalol (1.5 vs 1,0%, p<0,001. 1,1% vs 0,8%/100 personyears). There were no significant differences in CPR or sudden cardiac death. Conclusions This real-world data did not show increased mortality in sotalol-treated patients. Ventricular arrhythmias were relatively rare. Careful patient selection and follow-up probably reduce the proarrhythmic risk during sotalol-treatment.