Business processes as well as software systems face various changes during their lifetime. As they mutually influence each other, business processes and software systems have to be modified in co-evolution. Thus, to adequately predict the change impact, it is important to consider the complex mutual dependencies of both domains. However, existing approaches are limited to analyzing the change propagation in software systems or business processes in isolation. In this paper, we present a tool-supported approach to estimate the change propagation caused by a change request in business processes or software systems based on the software architecture and the process design. We focus on the mutual dependencies regarding the change propagation between both domains. In the evaluation, we apply our approach to a community case study to demonstrate the quality of results in terms of precision, recall, and coverage.