Post-puberal castration of calves is a common management practice in beef production systems. The methods and the age at which castration is performed are considered stressful conditions. The effects of both variables on performance and stress response of beef cattle were evaluated. Data of average daily gain and peak plasma cortisol concentration of calves castrated by surgical and rubber banding methods at different ages were analyzed. Castration-associated weight loss was evaluated within the first 30 days post-castration. The weight loss increased quadratically as the age of castration increased (P<0.01; R 2 =0.86) indicating that castration by any of the methods, at birth or close to birth, drastically reduces the weight loss. Surgical castration performed after puberty has an important detrimental effect on performance (P<0.01), which extends for a period beyond of the first 30 days post-castration. The average daily gain was not affected by the method of castration (P=0.9). Stress response in cattle ≤ 6 months of age tended to be lower (P=0.1) than that of cattle castrated at an age > 6 months. No statistical differences (P>0.05) were detected in stress response between surgical and rubber banding procedures. However, the fact that the lower stress response of intact cattle was not statistically different (P>0.05) from banded cattle suggests that rubber banding castration is less stressful than surgical castration.