Background Despite substantial investment in step-free access at UK railway stations, persons with reduced mobility (PRMs) continue to travel less than their able-bodied counterparts and little is known about the value of step-free access. This research examines the benefits of step-free access and its relationship with rail usage among PRMs, and the wider benefits of railway station accessibility. Methods These issues are explored through a mixed methods approach. Semi-structured interviews with ten key organisations were undertaken, as was an analysis of Senior/Disabled Persons Railcard data from 17 railway stations in Buckinghamshire, each with varying levels of step-free accessibility. Results The results show that the benefits of step-free access extend beyond benefits at the individual level typically associated with those limited to PRMs, and demonstrate the potential to positively affect the society at large economically, environmentally, and socially. The findings also show a positive correlation between the level of step-free accessibility at a railway station and the percentage of PRMs using it. Conclusions This research argues that government and interested stakeholders should commit to expanding the number and coverage of step-free stations throughout the UK. They should ensure that the appraisal process for investment in step-free accessibility appropriately captures both user and non-user benefits.