Recent research has questioned restrictive transfusion policies in vulnerable elderly populations. Our audit assesses the prevalence and postoperative outcomes of extremely elderly patients undergoing the stress of surgery with perioperative hemoglobin (Hb) less than 9 g/dL. This retrospective analysis of prospectively collected data addressed patients aged 85+ undergoing elective surgery. Demographic data and baseline characteristics were recorded, as well as Hb and transfused red blood cell (RBC) units. The main endpoint was the prevalence of perioperative Hb less than 9 g/dL, that is, patients with baseline Hb <9 g/dL without preoperative transfusions (defined as Group A). Patients with perioperative Hb of 9 g/dL or greater (with or without transfusion) were designated as Group B. Secondary outcomes included morbidity, length of hospital stay, and mortality 30 days and 6 months after surgery. A bivariate analysis was performed followed by logistic regression to determine whether undergoing the stress of surgery with perioperative Hb less than 9 g/dL was an independent risk factor for postoperative outcomes. A total of 148 patients were included. The prevalence of perioperative Hb less than 9 g/dL was 25%. It was associated with increased morbidity and mortality -both 30 days and 6 months after surgery- and a prolonged length of hospital stay. Anemia-associated complications were higher among patients from Group A, whereas transfusion-associated ones were evenly distributed. In all the regression models, perioperative Hb less than 9 g/dL was an independent risk factor for worse postoperative outcomes. Perioperative Hb less than 9 g/dL was common among patients aged 85+, and it was associated with increased risk of adverse postoperative outcomes. The tolerance to anemia might decrease perioperatively when Hb is less than 9 g/dL. Thus, less restrictive thresholds deserve further evaluation. © 2019 AABB.