To compare the use of topical tranexamic acid (TXA) with postoperative autologous transfusion (PAT) in terms of blood loss, need for allogeneic blood transfusion, and cost-effectiveness. Records of 25 men and 125 women (mean age, 67 years) who underwent primary unilateral total knee arthroplasty (TKA) and were randomised to the PAT group (n=50), topical TXA group (n=50), or routine drainage group (control) [n=50] were reviewed. Pre- and post-operative haemoglobin level, total postoperative drainage volume, and the need for allogeneic blood transfusion were recorded. The 3 groups were comparable in terms of age, gender, and preoperative haemoglobin level. The total postoperative drainage volume was lower in the TXA group than the PAT or routine drainage groups (174.48 vs. 735 vs. 760 ml, p<0.001). The postoperative haemoglobin level was lower in the routine drainage group than the PAT or TXA groups on day 1 (11.67 vs. 12.33 vs. 12.40 g/dl, p<0.001) and day 3 (9.9 vs. 10.7 vs. 11.14 g/dl, p<0.001). The number of patients who received allogeneic blood transfusion was higher in the routine drainage group (12 and 4 patients received 1 and 2 units of blood, respectively) than the PAT group (4 patients received 1 unit of blood) or the TXA group (none required transfusion) [p<0.001], and the respective total transfusion cost was $1200, $240, and $0. The total cost was lowest in the TXA group followed by the routine drainage group and PAT group ($200 vs. $1200 vs. $12 390). No patient developed acute infection, deep venous thrombosis, pulmonary embolism, myocardial infarction, or stroke. Compared with PAT, topical TXA was more cost-effective and resulted in less total postoperative drainage volume and less need for allogeneic blood transfusion.