Heterogeneous impacts of MaaS adoption on travel-time redistribution: implications for sustainable urban mobility planning

Mobility as a Service (MaaS) is expected to reshape urban mobility by integrating travel information, route planning, payment, and multimodal transport services. However, its behavioral and environmental impacts may differ across users with distinct mobility lifestyles. This study examines the heterogeneous effects of MaaS adoption on stated travel behaviour, travel-time redistribution across transport modes, and potential environmental benefits. Using survey data from 1000 adults in South Korea, this study applied K-means-based consensus clustering to identify mobility lifestyle segments, a multinomial logit model to examine segment characteristics, paired sample t-tests to compare travel-time changes under a hypothetical Level 2 MaaS scenario, and a diffusion-based environmental benefit evaluation to estimate CO2 emission changes. Six segments were identified: regular metro commuters, urban bus travelers, economical pedestrians, low-mobility users, family-oriented flexible drivers, and regional car commuters. The results show that MaaS adoption may reduce private car use while increasing public transportation, shared mobility, micromobility, walking, and total travel time. These changes suggest that MaaS redistributes travel demand across transport services rather than simply replacing private cars with a single alternative mode. The effects were segment-specific: MaaS may improve connectivity for public-transport-oriented users, enhance accessibility for low-mobility users, and substitute private car travel for car-dependent users. Environmental benefits were concentrated in car-dependent segments, and diffusion scenarios showed that adoption sequence matters. The findings suggest that MaaS policies should combine targeted diffusion and modal steering to enhance mobility while maximizing environmental benefits.