This project is a field experiment on Singapore’s subways and aims to evaluate the effectiveness of using reward schemes to incentivise peak-time commuters to travel pre-peak. In a randomised controlled trial design, frequent peak-time commuters in the treatment groups will receive rebates of their subway fare for traveling pre-peak. Some of them will receive a further bonus if their numbers of pre-peak trips reach a threshold. The monetary incentives are designed to be temporary, while our observation will cover the period after the discontinuation of the incentives. In a difference-in-differences analysis, we test (1) whether the promotional scheme shifts peak-time trips and (2) if so, whether the shifts persist beyond the promotional period.