This article presents an experimental, theory-driven evaluation of the effectiveness of an intervention that combines a free public transportation ticket and personal schedule information on the subsequent use of public transportation in an urban area. The time point when participants received this intervention is unusual. It was delivered to them shortly after a residential relocation. It is assumed that such a situation increases people's responsiveness to the intervention. At their new living place, the intervention group shows a strong increase in public transportation use. The intervention effect on the individual choice process is modeled via Ajzen's theory of planned behavior. Besides a main effect on intention, results indicate interactions between the intervention and the change intention existing prior to the move and higher objective public transport service quality after the move.