<p>Transplant center performance and practice variation for pediatric post-liver transplantation (LT) outcomes other than survival are understudied. This was a retrospective cohort study of pediatric LT recipients between 1/1/2006-5/31/2017 using United Network for Organ Sharing (UNOS) data that was merged with the Pediatric Health Information System database. Center effects at 1 year post-LT for acute rejection (AR1) using UNOS coding and biliary complications (BC1) using inpatient biling claims data were estimated by center-specific rescaled odds ratios that accounted for potential differences in recipient and donor characteristics. There were 2,216 pediatric LT recipients at 24 free-standing children's hospitals in the US during the study period. The median unadjusted center rate of AR1 was 36.92% (IQR: 22.36-44.52%), while that of BC1 was 32.29% (IQR: 26.14-40.44%). Accounting for recipient case-mix and donor factors, 5/24 centers performed better-than-expected with regards to AR1, while 3/24 centers performed worse-than-expected. There was less heterogeneity across the center effects for BC1 than for AR1. There was no relationship observed between center effects for AR1 or BC1 and center volume. CONCLUSION: Beyond recipient and allograft factors, differences in transplant center management are an important driver of center AR1 performance, and less so of BC1 performance. Further research is needed to identify the sources of variability so as to implement the most effective solutions to broadly enhance outcomes for pediatric LT recipients.</p>