It is widely discussed that the rural poor suffer seasonal starvation during the agricultural lean period. Unlike unanticipated shocks such as natural hazard and economic crisis, this seasonality appears to be anticipatable, hence would be manageable. To investigate whether time-locked commitment savings schemes can prevent the seasonal fall in consumption, we implement a randomized controlled trial to offer households commitment-savings products, either with market (8% per annum) or premium (50%) interest rates. We target 180 households with limited access to agricultural land that comprise the poorest segment in the Greater Rangpur region of northern Bangladesh. We pay particular attention to well-documented seasonal deprivation in the agricultural lean period from the mid-September to the end of October, locally known as Monga; households can receive the pre-specified interest if they can save money in the experimental account until Monga. To trace the impact of the commitment-saving product, we conduct bi-weekly surveys 18 times a year from April to January for two years, 2018/2019 and 2019/2020, where the first and second year correspond to pre- and post-intervention period, respectively.