The biochemical response to ursodeoxycholic acid (UDCA) in primary biliary cirrhosis is a strong predictor of long‐term outcome and thus facilitates the rapid identification of patients needing new therapeutic approaches. Numerous criteria for predicting outcome of treatment have been studied based on biochemical response to UDCA at 1 year. We sought to determine whether an earlier biochemical response at 3 or 6 months could as efficiently identify patients at risk of poor outcome, as defined by liver‐related death, liver transplantation, and complications of cirrhosis. We analyzed the prospectively collected data of 187 patients with a median follow‐up of 5.8 years (range, 1.3‐14 years). The survival rates without adverse outcome at 5 years and 10 years were 86% and 63%. Under UDCA therapy, laboratory liver parameters experienced the most prominent improvement in the first 3 months (P < 0.0001) and then stayed relatively stable for the following months. The Paris, Barcelona, Toronto, and Ehime definitions, but not the Rotterdam definition, applied at 3, 6, and 12 months significantly discriminated the patients in terms of long‐term outcome. Compared with biochemical responses evaluated after 1 year of UDCA therapy, biochemical responses at the third month demonstrated higher positive predictive value (PPV) but lower negative predictive value (NPV) and increased negative likelihood ratio (NLR) by all definitions; biochemical responses at the sixth month showed higher or the same PPV and NPV and lower NLR by all definitions. Conclusion: For the previously published criteria, biochemical responses at the sixth month can be used in place of those evaluated after 1 year of UDCA therapy. Our findings justify a more rapid identification of patients who need new therapeutic approaches. (HEPATOLOGY 2013)