The infaq (charity) feature on the ATM machines facilitates the costumers of Bank Syariah Mandiri to give charity. It is considered to be more effective and efficient especially for the costumers of Bank Syariah Mandiri. Therefore, this study aims to explore the factors influencing the costumers to give charity and their decision to give charity. This is a quantitative research using primary data obtained through a list of questions in the form of questionnaires and direct interviews with 100 respondents using convenience sampling. The costumers using ATM machines at Bank Mandiri Syariah KCP (sub-branch office) Magelang were selected to be the population of the research. The data were analysed using multiple linear regressions. The results show that the motivation and decision to give charity significantly affect the effectiveness of infaq facility on ATM machines toward Bank Syariah Mandiri costumers in Magelang.