BACKGROUND: Long-term outcomes of hepatitis B virus (HBV) nucleic acid test (NAT)-positive (+) allograft use in seronegative liver transplant (LT) and kidney transplant (KT) recipients remain unknown despite being incorporated into practice by select centers. This study compares long-term outcomes between HBV NAT+ and NAT-negative (-) allografts in seronegative recipients. STUDY DESIGN: All recipients of an HBV core antibody-positive (HBcAb+) LT or KT were prospectively evaluated at a single transplant center from June 2015 to March 2023 and compared by NAT status. Study endpoints were posttransplant viremia, patient, and graft survival. RESULTS: One hundred forty-four HBcAb+ LT and 220 HBcAb+ KT were performed including 57 (39.6%) NAT+ LTs and 123 (55.9%) NAT+ KTs with a median follow-up of 36 months. Approximately 14.8% of NAT+ and 3.5% of NAT- LTs experienced posttransplant viremia (p = 0.004). At the time of the last follow-up, 100% of NAT+ and 98.9% of NAT- LT recipients had undetectable HBV DNA (p = 0.31). Approximately 4.1% of NAT+ and 6.2% of NAT- KTs experienced posttransplant viremia (p = 0.12). At the time of the last follow-up, 100% of NAT+ and 96.9% of NAT- KT recipients had undetectable HBV DNA (p = 0.85). LT and KT patient and graft survival were not different between groups (p >
0.05). CONCLUSIONS: With close surveillance, HBV seronegative recipients transplanted with NAT+ allografts can develop viremia which can be cleared with antiviral therapy. This is the first and largest single-center study reporting longer-term experience with HBV NAT+ allografts in seronegative recipients demonstrating the safe expansion of the donor pool.