This work provides a scientific study on the constitutionality and legality of the economic and financial measures adopted by financial institutions in the period of exception experienced by the COVID-19 pandemic. Dialogue with constitutional principles seeks to understand the institute of anatocism in front of the reduction of inequalities, the promotion of material equality and the promotion of the constitutional principle of solidarity. Thus, the problem is to see how financial institutions have behaved the economic and social challenges of the current COVID-19 pandemic. And it is possible that many financial institutions are even promoting any change in their contractual terms and others, when they do so, do not promote any suspension of the penalty clauses of their respective contracts, or at most exempt themselves from the collection of monetary updates. Furthermore, the nature of the methodological aspect is qualitative, in view of the fact that the topic requires a broad and attentive knowledge of the new economic and social landscape caused by the COVID-19 pandemic. It uses the deductive approach method, the historical and monographic procedure method, as well as literature and documentary research techniques. Finally, the work seeks to emphasise that the aim is not to break an economic model imposed by capitalism, but to promote consumer protection in the form of Article 5 (XXXII of the Financial Code) and to ensure that losses are solidarity-based. It is not possible to imagine that specific segments can benefit disproportionately as they continue to print abusive bank charges and interest as they were in a normal scenario.