The role of context in behavioral interventions is indisputable, yet few intervention studies start with a systematic mapping of the influencing contextual factors. This is mostly due to the lack of a methodology that researchers can employ for this aim. Recognizing this current limitation of the field, we developed a procedure, the Choice Context Mapping, to provide researchers a tool to examine the contextual factors of a targeted behavior. We demonstrate the steps of Choice Context Mapping on the behavioural choice situation of stairs vs. elevator use. Potential contextual factors were collected from laypeople as well as experts, and two surveys were created to measure both the behavior and choice, as well as the beliefs of participants. We estimated the effect of contextual factors on the participants’ behavior and managed to identify the most influential ones regarding their contribution to the studied choice. Using Choice Context Mapping, we obtained an accurate prediction of whether one chooses the stairs or elevator based on contextual information in 93.26% of the cases, on previously unseen data. We also ascertained that participants differed in their beliefs about what influences them in this particular choice, and that they can be divided into different groups based on their beliefs. Our results indicate that Choice Context Mapping is a useful procedure for the collection and assessment of contextual factors in a given choice setting which can help the planning of behavioral interventions by considerably lowering the number of possible interventions that are plausibly effective.