Certain patient groups are predicted to derive significant survival benefit from transplantation with expanded criteria donor (ECD) kidneys. An algorithm published in 2005 by Merion and colleagues characterizes this group: older adults, diabetics and registrants at centers with long waiting times. Our goal was to evaluate ECD listing practice patterns in the United States in terms of these characteristics. We reviewed 142 907 first-time deceased donor kidney registrants reported to United Network for Organ Sharing (UNOS) between 2003 and 2008. Of registrants predicted to benefit from ECD transplantation according to the Merion algorithm ('ECD-benefit'), 49.8% were listed for ECD offers ('ECD-willing'), with proportions ranging from 0% to 100% by transplant center. In contrast, 67.6% of adults over the age of 65 years were ECD-willing, also ranging from 0% to 100% by center. In multivariate models, neither diabetes nor center waiting time was significantly associated with ECD-willingness in any subgroup. From the time of initial registration, irrespective of eventual transplantation, ECD-willingness was associated with a significant adjusted survival advantage in the ECD-benefit group (HR for death 0.88, p < 0.001) and in older adults (HR 0.89, p < 0.001), but an increased mortality in non-ECD-benefit registrants (HR 1.11, p < 0.001). In conclusion, ECD listing practices are widely varied and not consistent with published recommendations, a pattern that may disenfranchise certain transplant registrants.