Transportation planners consider travel as derived demand to execute various activities at destinations. Here what is important is ‘activity’. Travel is just a necessary act to perform the activity. Thus, travel time is considered as a sort of opportunity cost, a time that is wasted. In that context, the ultimate objective of building a new transport infrastructure is to shorten travel time for citizens. However, since everybody owns and uses smartphones these days, whether citizens of Seoul can find some utilities while traveling and doing a range of activities (such as reading news, watching dramas and listening to music) is controversial. In particular, if there are people who study or work during travel to work, it means that travel time is being productively used. That goes against the traditional assumption in transportation field that travel time is wasted. To counter such an assumption, this study predicts monetary values of activities during commuting to work. Using the Contingent Valuation Method (CVM), the authors asked 1,000 citizens of Seoul as to what they did while traveling to work and how much they would pay to continue their activities during traveling. Our analysis predicts that drivers, subway users and bus riders are willing to pay for 9,278, 7,963 and 5,475 Won/hour·month, respectively. For instance, a person who travels to work for 2 hours every day using subway would be willing to pay for 16,000 Won a month. This result provides a useful information to evaluate current transportation policies.