This is the report of a midline evaluation of a randomized controlled trial to increase the utilization of saving and other financial services by women business owners in Indonesia. The trial was motivated by a recent law in Indonesia supporting the development of branchless banking services for a large unbanked rural population and by the results of several studies suggesting that it is possible to stimulate savings and improve a range of downstream outcomes with suitable interventions targeted to under-banked rural populations. The trial was conducted in 400 purposively selected rural and semi-urban villages in five districts of East Java province in which branchless banking services (including basic savings accounts accessible through mobile phones) were available. The randomized interventions supported by this trial include both supply-side treatments (higher agent incentives) and demand-side treatments (training and mentoring of female business owners). The data analyzed include both baseline and midline survey data on female and male business owners and branchless banking agents. Implementation of the trial was delayed due to difficulties in recruiting suitable agents in all 400 trial villages. Numerous supply-side problems, both technical and logistical, were also reported in the monitoring data. However, the midline results indicate that the interventions were successfully delivered, resulting in significant positive effects on key intermediate outcomes, including knowledge and use of mobile banking services and initial take up of a mobile basic savings account. Downstream effects indicate that the supply- and demand-side interventions, particularly in combination, increased women business owners’ savings, empowerment, self-confidence, and economic welfare.