Abstract Patients with myelodysplastic syndromes (MDS) frequently become dependent on blood transfusions. We analyzed the total transfusion support required, and its complications and cost, following the diagnosis of MDS (total period=79.7 patient-years) in 50 patients followed at the Minneapolis VA Medical Center. From diagnosis of MDS to transformation to AML or death (the MDS phase), 41 patients (82%) required transfusions. The median numbers of transfused blood products per patient per year of follow-up in the MDS phase were: packed red blood cells (pRBC), 11.1 (range, 0–91.3) units, random donor platelets (RDP), 6.8 (range, 0–581) units, and single donor apheresis platelet packs (SDP): 0 (range, 0–40) collections. In the AML phase (time from diagnosis of secondary AML to death or last follow-up), median transfusion requirements per patient ( n=5) were 24 (range, 8–88) units pRBC, 94 (range, 24–480) units RDP and 3 (range, 0–19) collections of SDP. Overall, 80% of patients required either special processing or selection of blood products, had reactions to blood products or required premedications (specified/complicated transfusions); 94% of all pRBC and 97% of all platelet transfusions were specified/complicated. The median cost of transfusions per patient was $4048 (range, $0–73 210) during the MDS phase and $13 210 (range, $5288–59 010) during the AML phase. During the MDS phase, the median cost was $4877 (range, $0–67 050) per patient-year of follow-up; the major proportion of this cost was for pRBC transfusions. Long-term support with frequent transfusions for MDS usually requires specially selected or processed blood products, and is associated with a high incidence of transfusion reactions. This study provides baseline data on the costs of transfusion support for MDS, and can be used for comparing resource utilization and costs of long-term transfusion support (supportive care) with growth factor therapy or disease-modifying modalities such as allogeneic transplantation.