Background J‐waves and fragmented QRS (fQRS) on surface ECGs have been associated with the occurrence of ventricular tachyarrhythmias. Whether these non‐invasive parameters can also predict ventricular tachycardia (VT) recurrence after radiofrequency catheter ablation (RFCA) is unknown. Of interest, patients with a wide QRS‐complex have been excluded from clinical studies on J‐waves, although a J‐wave like pattern has been described for wide QRS. Methods We retrospectively included 168 patients (67 ± 10 years; 146 men) who underwent RFCA of post‐infarct VT. J‐wave pattern were defined as J‐point elevation ≥ 0.1 mV in at least two leads irrespective of QRS width. fQRS was defined as various RSR` pattern in patients with narrow QRS and more than two R wave in those with wide QRS. The primary endpoint was VT recurrence after RFCA up to 24 months. Results J‐wave pattern and fQRS were present in 27 and 28 patients, respectively. Overlap of J‐wave pattern and fQRS was observed in nine. During a median follow‐up of 20 (interquartile range 9–24) months, 46 (27%) patients had VT recurrence. Kaplan–Meier curves revealed that both J‐wave pattern and fQRS were associated with VT recurrence. Multivariate Cox regression analysis demonstrated that the presence of J‐wave pattern (hazard ratio HR 2.84; 95% confidence interval CI 1.45–5.58; P = .002) and greater number of induced VT (HR 1.29; 95% CI 1.15–1.45; P < .001) were the independent predictors of VT recurrence. Conclusions A J‐wave pattern—but not fQRS—is independently associated with an increased risk of post‐infarct VT recurrence after RFCA irrespective of QRS width. This simple non‐invasive parameter may identify patients who require additional treatment.