The impact of atrial fibrillation (AF) catheter ablation versus chronic antiarrhythmic therapy alone on clinical outcomes such as death and stroke remains unclear. We compared adverse outcomes for AF ablation versus chronic antiarrhythmic therapy in 1,070 adults with AF treated between 2010 and 2014 in the Kaiser Permanente Northern California and Southern California healthcare delivery systems. Patients who underwent AF catheter ablation were matched to patients treated with only antiarrhythmic medications, based on age, gender, history of heart failure, history of coronary heart disease, history of hypertension, history of diabetes, and high-dimensional propensity score. We compared crude and adjusted rates of death, ischemic stroke or transient ischemic attack, intracranial hemorrhage, and hospitalization. The matched cohort of 535 patients treated with AF ablation and 535 treated with antiarrhythmic therapy had a median follow-up of 2.0 (interquartile range 1.1 to 3.5) years. There was no significant difference in adjusted rates of death (adjusted hazard ratio [HR] 0.24, 95% confidence interval [CI] 0.03 to 1.95), intracranial hemorrhage (adjusted HR 0.17, CI 0.02 to 1.71), ischemic stroke or transient ischemic attack (adjusted HR 0.53, CI 0.18 to 1.60), and heart failure hospitalization (adjusted HR 0.85, CI 0.34 to 2.12), although there was a trend toward improvement in these outcomes with ablation. However, there was a significantly increased risk of all-cause hospitalization following ablation (adjusted HR 1.60, CI 1.25 to 2.05). In a contemporary, multicenter, propensity-matched observational cohort, AF ablation was not significantly associated with death, intracranial hemorrhage, ischemic stroke or transient ischemic attack, or heart failure hospitalization, but was associated with a higher rate of all cause-hospitalization.