Purpose <p>Canadian guidelines suggest that physicians should consider prescribing four weeks of oral anticoagulation (OAC) for patients undergoing cardioversion for acute atrial fibrillation/flutter (AF/AFL), regardless of stroke risk. While the risk of stroke following cardioversion may be low, the morbidity and cost from a stroke is significant. This study aims to evaluate the cost-effectiveness of routinely providing OAC after cardioversion.</p> Methods <p>We conducted a cost-utility analysis comparing no-OAC post-cardioversion to four weeks of OAC, from the perspective of the Canadian public payer, in adults with acute AF/AFL and no risk factors based on the CCS Algorithm (CHADS-65). A decision tree was used to estimate clinical outcomes, quality-of-life, and costs. Results were expressed as quality-adjusted life days and an incremental net monetary benefit. We performed a probabilistic sensitivity analysis using 10,000 Monte Carlo simulations to assess the robustness of our findings.</p> Results <p>No-OAC was found to be dominant, with slightly increased quality-of-life (296 quality-adjusted life days vs. 295 quality-adjusted life days) at a lower cost [CAN$108.86 (95%CI $107.38-$110.34) vs. CAN$117.73 (95%CI $116.54-$118.91)] and an incremental net monetary benefit of $25.22 (95%CI $19.21-$31.23). A probabilistic sensitivity analysis showed the no-OAC option was cost-effective in 69.5% iterations. The results were driven by low event rates post-cardioversion.</p> Conclusion <p>There were minimal differences between strategies and forgoing anticoagulation resulted in very slight improvement in quality-of-life at a reduced cost. We hope this provides guidance to physicians and look to see this evidence incorporated into Canadian guidelines for atrial fibrillation.</p>