Determinants of Fare-Free Public Transport Demand Among Older Adults: Evidence from Nationwide Smart-Card Data

Fare-free public transport policies are widely implemented to improve accessibility for older adults, yet their effects vary across spatial contexts. Population ageing further increases the need for accessible mobility, while intelligent transport systems (ITS) enable the use of large-scale operational data for evidence-based transport planning. This study examines the determinants of fare-free public transport demand using nationwide smart-card validation data from Slovenia, where free travel for residents aged 65 and over was introduced in 2020. The analysis combines IJPP smart-card data with selected socio-economic, service-level and spatial indicators and applies bivariate correlation and regression analysis at the regional level. The results reveal substantial regional variation in demand intensity. Service availability shows the strongest positive association with usage, while car ownership exhibits a moderate negative relationship. In contrast, economic indicators and population density show limited explanatory power. These findings indicate that differences in realised demand are primarily shaped by service and accessibility conditions rather than pricing alone. The study highlights the importance of integrating fare policies with service provision when planning mobility systems in ageing societies.