The present study sought to estimate the incidence and evaluate the patterns and associations of systemic venous anomalies in patients with tetralogy of Fallot on multidetector computed tomography (CT) angiography. We retrospectively reviewed CT angiographies of 973 pediatric age group patients diagnosed with tetralogy of Fallot, performed at our institution between 1st January 2015 and 31st December 2019, for systemic venous drainage patterns. We also proposed a structured classification and reporting system on CT angiography which would simplify the characterization, classification, and communication of these anomalies. Variations in systemic venous drainage patterns were observed in 146 (15.01%) patients. The most commonly observed anomaly was persistence of left superior caval vein, which was seen in 112 (11.51%) patients, with the most prevalent pattern being the presence of bilateral superior caval veins with no intercommunicating vein (n = 85). The second most common anomaly observed was presence of anomalous brachiocephalic vein (39/973 [4.01%]). Patients with an anomalous course of brachiocephalic vein had significantly higher prevalence of a right aortic arch than those without (23/39 [58.97%] vs 188/934 [20.13%]; P < .0001). Similarly, a higher prevalence of pulmonary atresia was noted in patients with an anomalous course of brachiocephalic vein compared to those without (8/39 [20.51%] vs 80/934 [8.57%]; P = .0109). There is a high incidence of anomalies of superior caval veins and brachiocephalic vein in the presence of tetralogy of Fallot. With advancements in corrective cardiac surgery and use of intraoperative cardiopulmonary bypass, the presence of systemic venous anomalies assumes greater significance making preoperative identification of these anomalies imperative.