According to the theories of reasoned action and planned behavior, the precedent to any human conduct is the intention to display such conduct. People’s attitudes are one of those precedents. Our work is framed within this line of research, as it seeks to analyze and explain the main determinants of attitudes towards boycotts. Thus, we understand that consumers’ attitudes towards boycott behavior depend on three fundamental beliefs: perceived legitimacy of the behavior, ethical idealism towards such behavior, and finally, ethical relativism towards boycott behavior. We emphasize legitimacy since the relevance of legitimacy processes in the businessclient relationship lies in the validation of actions that allows their subjective recognition and, therefore, differentiates them from the legal nature of the acts. The research is carried out with 371 people and the hypotheses presented are verified through structural equation models. Discussion of the results and their implications contribute to a better understanding of the factors that determine the attitudes towards customer boycotts by business managers and academics.