IntroductionCatheter ablation for atrial fibrillation (AF) reduces symptoms and improves the quality of life compared with medical treatment. It is unclear if frailty impacts on the outcome of catheter ablation in patients with symptomatic AF. We sought to evaluate the association between frailty as measured by the validated NHS electronic Frailty Index (eFI) and outcomes post‐AF ablation.MethodsTwo hundred forty eight patients who had undergone AF ablation with a mean age of 72.9 ± 5.16 were included in the study retrospectively. The primary endpoint for success was defined as freedom from atrial arrhythmia lasting >30 s beyond the 3‐month blanking periods. Frailty was based on the eFI, and the cohort split into four groups: fit (no frailty), mild, moderate and severe frailty.ResultsFrailty was categorized as fit (118/248; 47.6%), mild (66/248; 26.6%), moderate (54/248; 21.8%), and severe (10/248; 4.0%). Freedom from arrhythmia occurred in 167 of 248 (67.3%) patients after a mean follow‐up of 25.8 +/– 17.3 months. Fit patients had significantly greater freedom from arrhythmia (92/118; 78%) compared to mild frailty (40/66; 60.6%, p‐value = .020), moderate frailty (31/54; 57.4%, p‐value = .006), or severe frailty (4/10; 40.0%, p‐value < .001). There was also a significant difference in arrhythmia occurrence between patients with mild frailty and severe frailty (p‐value = .044).ConclusionFrailty is associated with poorer outcomes in patients undergoing AF ablation. The eFI may be used in the prognostic evaluation of AF ablation outcomes. Further studies are essential to confirm the findings of this study.