Some clients focus on the service quality, associated risk and the financial impact of the bank whereas other clients prefer to select the bank on the basis of their religiosity. The main objective of this study is to explore the reasons of the bank selection by the clients. This study also tries to explore the impact of the rationality and religiosity on the adoption of Islamic banks in the presence of the perception that both banks are similar. We applied mixed method approach. At first stage, in-depth interviews were conducted for the qualitative judgment of the problem and then quantitative approach was used by collecting data through questionnaires. Structural equation modeling was applied by using AMOS and SPSS. Results indicate that both religiosity and rationality have positive impact on selection of Islamic banks but, in the presence of rationality, religiosity is having insignificant influence. Perception about the similarity of both types of banks reduces the impact of religiosity on adoption of Islamic banks. However, this perception does not have any impact on the relationship of rationality with adoption of Islamic banks because the rational clients don’t bother about the similarity of bank types.