Objectives: This study aims to evaluate the effect of intraarticular tranexamic acid (TA) administration on the amount of blood in the drains, the amount of blood transfusion, length of hospital stay, and the total cost in total knee arthroplasty (TKA) patients. Patients and methods: The study included a total of 118 patients (24 males, 94 females; mean age 67.0 years, range 52 to 81 years) who underwent primary unilateral TKA surgery. Patients were divided into two groups as 58 patients who were performed intra-articular injection of 2 g TA after closure of articular capsule (TA group; 10 males, 48 females, mean age 65.6 years; range 55 to 80 years) and 60 patients who were not performed any intra-articular injection (non-TA group; 14 males, 46 females; mean age 68.3 years; range 52 to 81 years). The maximum difference between pre- and postoperative hemoglobin levels, the amount of blood in the drains, the amount of blood transfusion, length of hospital stay, and cost of each patient were recorded. Results: The mean difference between pre- and postoperative hemoglobin levels were higher in the non-TA group (1.7 g/dL vs 2.6 g/dL, p < 0.05). The mean amounts of blood in drains (327.5 mL vs 800.0 mL, p < 0.05), the amounts of blood transfusions (0 units vs 10 units, p < 0.05), the mean lengths of hospital stay (4.03 days vs 4.53 days, p < 0.05), and the hospital costs (1,935.26 United States dollars vs 1,959.64 United States dollars, p < 0.05) were lower in TA group. Conclusion: Administration of intra-articular TA during primary TKA may reduce blood loss and the need for blood transfusion while significantly shortening the postoperative length of hospital stay and reducing the total hospital costs.