Travel time is one of the most fundamental and important determinants of travel behavior. However, the travel time on which a travel decision is based is a subjective one (i.e., it is an anticipated travel time). A conceptual model of the formation of an anticipated travel time through information acquisition and initial driving experience is proposed. Day-to-day data of anticipated travel times were collected during a closure of the Hanshin Expressway Sakai Route, a toll road connecting the central business districts of Osaka and Sakai, which is located approximately 20 km south of the Osaka route closure. A test was conducted of the information dominance hypothesis (i.e., as drivers acquire more information on travel time, they can predict travel time more precisely and refer less to anticipated travel times used in the past to anticipate travel times) and the experience dominance hypothesis (i.e., influences of information not from driving experience on anticipated travel time is weaker with actual driving experience than without actual experience). Although word of mouth information does not have impacts consistent with these two hypotheses, results with other types of information support both hypotheses.