With the growing popularity of mobile commerce (m-commerce), it becomes vital for both researchers and practitioners to understand consumers’ mobile commerce adoption behavior. In this study, we empirically investigate the drivers of consumers’ mobile commerce adoption behavior based on a cost and benefit framework. Based on consumers' browsing and purchase behaviors at the e-commerce site before the addition of mobile commerce channel, we constructed behavioral proxy variables which capture the underlying cost and benefit of mobile commerce channel relative to the pre-existing e-commerce channel. We collected two large datasets from of a large e-marketplace in South Korea that introduced mcommerce to its existing e-commerce offering in 2011. Based on the analysis of browsing and purchase behaviors of 29,283 subjects over a period of 28 months, we find that the need for ubiquity plays a significant role in the m-commerce adoption decision. The two proxies for ubiquity need— Purchase frequency and Purchase time irregularity—were found to have a positive impact on mcommerce adoption. The results also suggest that search cost influences the decision to adopt mcommerce. Specifically, we find that the consumers who search multi-item or categories at a time, engage in active search, and conduct thorough search, are less likely to adopt m-commerce. Finally, the results show that the risk preference of the consumer is related to the adoption decision. Risk aversion, as measured by the two proxies—Reliance on secure log-in system, and Need for receiving confirmations—lowers the likelihood of m-commerce adoption. These results highlight the importance of the unique features of mobile platform in influencing the consumers’ adoption of m-commerce. We discuss the implications of our findings for academics and practitioners.