Blood loss, operative time, and rate of complications were compared in 606 patients undergoing primary unilateral total hip arthroplasty with either spinal anesthesia (SA) or general anesthesia (GA). Patients were followed for 2 years after surgery. Compared with GA, SA resulted in mean reductions of 12% in operative time, 25% in estimated intraoperative blood loss, 38% in rate of operative blood loss, and 50% in intraoperative transfusion requirements. Compared with patients receiving GA, patients receiving SA had higher hemoglobin levels on postoperative days 1 and 2 and a 20% lower total transfusion requirement. SA appears superior to GA for this procedure.