Cirrhotic cardiomyopathy (CCM), a comorbidity of end‐stage cirrhotic liver disease, remains uncharacterized in children, largely because of a lack of an established pediatric definition. The aim of this retrospective cohort analysis is to derive objective two‐dimensional echocardiographic (2DE) criteria to define CCM associated with biliary atresia (BA), or BA‐CCM, and correlate presence of BA‐CCM with liver transplant (LT) outcomes in this population. Using receiver operating characteristic (ROC) curve analysis, optimal cut‐off values for left ventricular (LV) geometrical parameters that were highly sensitive and specific for the primary outcomes: A composite of serious adverse events (CSAE) and peritransplant death were determined. These results were used to propose a working definition for BA‐CCM: (1) LV mass index (LVMI) ≥95 g/m2.7 or (2) relative wall thickness of LV ≥0.42. Applying these criteria, BA‐CCM was found in 34 of 69 (49%) patients with BA listed for LT and was associated with increased multiorgan dysfunction, mechanical and vasopressor support, and longer intensive care unit (ICU) and hospital stays. BA‐CCM was present in all 4 waitlist deaths, 7 posttransplant deaths, and 20 patients with a CSAE (P < 0.01). On multivariable regression analysis, BA‐CCM remained independently associated with both death and a CSAE (P < 0.01). Utilizing ROC analysis, LVMI was found to be a stronger predictor for adverse outcomes compared with current well‐established markers, including Pediatric End‐Stage Liver Disease (PELD) score. Conclusion: BA‐CCM is highly sensitive and specific for morbidity and mortality in children with BA listed for LT. 2DE screening for BA‐CCM may provide pertinent clinical information for prioritization and optimal peritransplant management of these children.