The Changing Paradigm of Good Samaritan Kidney Donation in the United States

Background. The practice of living donor kidney transplantation has evolved through innovations in logistics, technology, and clinical practice. In the United States, Good Samaritan donation, a historical label exclusive to nondirected donors, now incorporates voucher-based models. Methods. To determine how voucher-based nondirected living kidney donation has influenced the volume and practice of Good Samaritan living kidney donation in the United States, we analyzed living donor kidney transplants from 2000 to 2024 using data from the National Kidney Registry (103 transplant centers) and the Scientific Registry of Transplant Recipients. Temporal trends were derived by linear regression. Results. We identified 4662 Good Samaritan living donor kidney transplants, defined as historical nondirected and novel voucher-based nondirected donations. Of 2131 Good Samaritan living donor kidney transplants facilitated by the National Kidney Registry, donors had a median age of 43 y, were predominantly of White race (93%), and were women (60%). Recipients had a median age of 52 y and were racially and ethnically diverse (63% White, 14% Black, and 10% Hispanic). Annual Good Samaritan donation counts in the United States increased from 17 in 2000 to 439 in 2024, corresponding to a growth rate of 14.5%. Voucher-based nondirected donations increased from 2 in 2015 to 314 in 2024, comprising 72% of all Good Samaritan donations in that year. Conclusions. The advent of voucher-based nondirected donation correlated with growth in Good Samaritan donation volume. Given the prevalence of voucher-based donations, connecting local kidney paired donation practices to voucher-based nondirected donation may improve access to and participation in living kidney donation.