The “FSW Assisted Bank Account” is an instrument used in the homeless assistance sector to secure essential expenses for rent, energy and other fixed costs and to “protect” them from spontaneous access by users. The project aims to increase the use and acceptance of the Assisted Bank Account so that as many potential users as possible can benefit from it. In addition, the tool will be analyzed and optimized using the behavioral economics approach in order to maximize its potential. The first step will be a systematic analysis of the status quo. We will use qualitative interviews to examine the interaction between the users of the Assisted Bank Account, the FSW Assisted Bank Account team, and the social workers who assist the users. Based on this analysis and using tools from the behavioral economics approach, we will develop interventions to increase the use and acceptance of the Assisted Bank Account. In addition, the functionality and effectiveness of the Assisted Bank Account shall be increased by improving processes and communication channels, with the goal of improving the financial health of its users. In a final step, we plan to test the effectiveness and acceptance of a selection of the developed measures in an experimental setting. The concrete selection and optimization of the interventions will be carried out in close coordination with the project partners and on the basis of the knowledge gained in the previous project steps. As part of the dissemination, the results will be widely communicated both in the scientific community and in practice.