BACKGROUND: To investigate the impact of residual lesion score (RLS) on the long-term outcomes of 5 common congenital heart operations. METHODS: All infants who underwent definitive surgery for complete atrioventricular septal defect (AVSD), tetralogy of Fallot (TOF), dextro-transposition of the great arteries (d-TGA), single ventricle (Norwood procedure), and coarctation with ventricular septal defect (CoA/VSD) between 2000 and 2012 who survived until discharge were studied. RLS scores (1 - no/trivial, 2 - minor, 3 - major or in-hospital reinterventions/reoperations for such lesions) were assigned based on post-repair clinical and echocardiographic evaluation. The time to events was summarized using the Kaplan-Meier survival method and competing risk models. RESULTS: 1027 patients were included (213 AVSDs, 358 TOFs, 308 d-TGAs, 127 single ventricles, and 21 CoA/VSDs) with a median follow-up time of 15 years (IQR 11-18.4 years). Overall, 227 patients (22.1%) had RLS of 1, 556 patients (54.1%) had RLS of 2, and 244 patients (23.8%) had RLS of 3. Freedom from late death/transplantation was 93.7% at 15 years. RLS was not associated with late death/transplantation. Male sex, TOF and ASO had the lowest risk for late death/transplantation. Late reintervention/reoperations were present in 14.5% at 15 years. Younger age, TOF/PS repair, ASO, RLS of 3 (HR 2.02, CI 1.17-3.51, p=0.012), intraoperative surgical revision, and in-hospital reintervention/reoperation associated with late reintervention/reoperation. CONCLUSIONS: The RLS does not predict late mortality but predicts late reintervention/reoperation after congenital cardiac repair and can be used to target at-risk patients for follow-up.