Background and ObjectivesSolid organ transplant surgeries including liver transplants constitute a substantial risk of bleeding complications and given frequent national blood shortages, supporting D‐negative transplant recipients with D‐negative red blood cell products perioperatively can be difficult for the transfusion services. This study was designed to compare the incidence of alloimmunization after D‐mismatched red cell transfusions between patients with and without a history of solid organ transplant at a single tertiary care hospital. The patients undergoing solid organ transplants are on strong immunosuppressive regimens perioperatively to help reduce the risk of rejection. We hypothesized that the use of these immunosuppressive agents makes these patients very less likely to mount an immune response and form anti‐D antibodies when exposed to the D‐positive red blood cell products perioperatively.Study Design and MethodsAt our center, D‐negative patients who received ≥1 unit of D‐positive red blood cell products were identified using historical transfusion records. Antibody testing results were examined to determine the incidence of the formation of anti‐D and any other red cell alloantibodies after transfusion and these results were compared between patients with and without a history of solid organ transplant.ResultsWe were able to identify a total of 22 patients over 10 years with D‐negative phenotype who had undergone a solid organ transplant and had received D‐positive red blood cell products during the transplant surgeries. We also identified a second group of 54 patients with D‐negative phenotype who had received D‐positive red blood cell products for other indications including medical and surgical.A comparison of the data showed no new anti‐D formation among patients with a history of D mismatched transfusion during solid organ transplant surgeries.ConclusionAmong our limited study population, we observed a very low likelihood of D alloimmunization among solid organ transplant recipients. A larger, prospective study could help further evaluate the need for prophylactic D matching for red cell transfusions during solid organ transplant surgeries.