Does the integrated fare policy strengthen the synergy between micromobility and mass public transit: A multimodal travel pattern analysis in Seoul

Seoul, South Korea launched the Climate Companion Card in 2024, a citywide integrated fare that offers unlimited subway and bus travel with an option to include the public shared bicycle. The policy was designed to strengthen micromobility–transit pairing for first- and last-mile trips. Using a 24-month station-level panel from January-December 2023 and January-December 2024, this study examines how the relationship between shared bicycle demand and nearby public transit intensity changed during the policy period. We combine spatial econometric models with station fixed-effects panel models and month-specific interaction profiles. The spatial models show that shared bicycle demand remains strongly clustered across nearby stations and that neighboring transit-rich areas exert competitive pressure on local bicycle demand. The fixed-effects estimates indicate a negative post-policy shift in the subway-bicycle linkage for both origin and destination demand. Month-specific estimates confirm that this weaker linkage is not driven by a single month, although individual monthly estimates remain imprecise. Overall, the findings suggest that fare integration alone did not uniformly strengthen micromobility–transit connections in Seoul.