Background Atrial tachyarrhythmias (ATAs) are common within the three-month blanking period following catheter ablation of atrial fibrillation (AF). However, little evidence is available regarding the current guidelines on the blanking period after surgical AF ablation. We investigate the incidence and significance of early recurrence of atrial tachyarrhythmia (ERAT) and evaluate the optimal blanking period after surgical AF ablation. Methods Data from 259 patients who underwent surgical AF ablation from 2009 to 2016 were collected. ERAT was defined as documented ATA episodes lasting for 30 seconds. A multivariate Cox proportional hazard model was constructed to evaluate the role of ERAT as a predictor of late recurrences (LR) for AF. Results In total, 127 patients (49.0%) experienced their last episodes of ERAT during the first (n=65), second (n=14), or third (n=48) month of the three-month blanking period (p<0.001). One-year freedom from ATAs was 97.8% in patients without ERAT compared with 95.4%, 64.3%, and 8.3% in patients with ERAT in the first, second, and third month after the index procedure, respectively (p<0.001). Hazard ratios of LR according to the timing of the last episode of ERAT first, second, and third month after the procedure were 2.84, 16.70, and 119.75, respectively. Conclusions The ERAT occurred in 49.0% of patients within the first three months after surgical ablation. The occurrence of ERAT within three months after surgical AF ablation was a significant independent predictor of LR. Hence, the currently accepted three-month blanking period needs to be redefined in patients with AF surgical ablation.