Among the tasks to investigate decisional processes, the Iowa Gambling Task (IGT) appears to be the most effective since it offers the opportunity to deepen the progressive learning process based on feedbacks derived by previous choices. Recently, the study of decision making through the IGT has been combined with the application of the transcranial direct current stimulation (tDCS) to further deepen the cognitive mechanisms and the neural structures involved. This scoping review wants to provide a comprehensive exploration of the effects of tDCS in modulating decisional processes assessed through the IGT, offering an analysis of the state of literature. Results highlighted a pivotal role of the dorsolateral prefrontal cortex and the orbitofrontal cortex in risky and ambiguous decisions. Overall, tDCS improved decisional processes in healthy subjects and patients, confirming its potential in enhancing decision making in everyday contexts. Suggestions for further studies are provided to delve into decisional mechanisms and how to better support them.