The high doses of chemotherapy used for the preparatory regimens before autologous blood or marrow stem cell transplantation leave patients at risk for neutropenic complications. The administration of filgrastim post transplant reduces the time to neutrophil recovery and therefore has become a standard practice at many institutions. In 2006, we implemented a practice change from filgrastim to pegfilgrastim. We present data on 164 consecutive patients (82 patients who received filgrastim compared with 82 patients who received pegfilgrastim) who received an auto-SCT between January 2006 and November 2007. Patients who received pegfilgrastim had faster engraftment (9.6 days compared with 10.9 days, P<0.0001), a lower incidence of febrile neutropenia (59% compared with 78%, P=0.015), as well as shorter hospital stay, fewer days of treatment with i.v. antibiotics (6.3 days compared with 9.6 days, P=0.006), and fewer radiographic tests, which translated to an estimated total cost savings of over $8000 per patient. Overall, there were no differences in toxicity with these two agents. We conclude that a single dose of pegfilgrastim is a safe and efficacious alternative to daily injections of filgrastim and can be a cost-effective approach in auto-SCT patients.