How would consumers respond to mobile ads in spatially and temporally bounded captive environments? We theorize that consumers who are forced to wait are likely to perceive an abundance of time and ultimately become more responsive to mobile ads. To test our theory, we conducted three studies following a multimethod approach. In Study 1, a large-scale field study (n = 66,473), we found a relationship between captivity and receptiveness to mobile ads in transit. In Study 2, a lab experiment, we extended our findings by revealing that time perception mediated the relationship between captivity and intention to click on mobile ads. Last, in Study 3, we tested boredom and individual propensities to use time efficiently as underlying mediating and moderating conditions for captivity's effect. Overall, the results have implications for advertising practitioners and researchers examining context-based mobile targeting.