Extended criteria donor (ECD) liver allografts are often allocated to less severely ill liver transplant (LT) candidates who are at a relatively lower risk of pretransplant mortality, but it is not clear that the use of ECD allografts will decrease center waitlist mortality (WLM). Individual patient data from the UNOS OPTN database (2002-2005) were aggregated to obtain center-specific data. Deceased donor allografts with any of the following characteristics were defined as ECDs: from a donor with any of the criteria described by the New York State Department of Health Workgroup; or 12+ h of cold ischemia. Multivariate regression was used to examine the relationship between WLM and ECD, non-ECD and LDLT use after adjusting for candidate severity of illness. A total of 3555 ECD transplants, 11,660 standard criteria donor (SCD) transplants, and 717 LDLTs were performed at 100 centers during this period. The model demonstrated that SCD and ECD LTs were inversely correlated with a center's WLM (beta=-0.242 and -0.221, respectively; p <or= 0.003 for each). LDLTs did not significantly reduce WLM (beta=-0.048, p=0.55). In summary, increasing ECD liver allograft use significantly decreased WLM at US centers. Policies encouraging the increase used of ECDs would further reduce WLM.