This article's main idea is analyze the benefit of royal grants in Navarre in exchange for money during the last two years of the reign of Felipe IV (1621-1665) and the reign of Carlos II of Austria (1665-1700), thus revealing a detailed list of buyers, the amounts paid and the type of grants purchased. For this, we have mainly used the Libros de Mercedes Reales, a record where most of the sales in which we are interested were recorded. To understand the whole process, it has been necessary a previous contextualization, for which we have employ the documentation of the Tesoreria de la Camara de Comptos, sections of Tribunales Reales, Actas de las Cortes and Actas de la Diputacion de Navarra (guarded in the Archivo Real y General de Navarra), as well as Libros de Navarra from the Archivo Historico Nacional (Madrid). All these sources, supported by the existing bibliography, have allowed us to carry out a small but useful synthesis on the state of the Royal Treasury in Navarre during the referred chronology to recognize its possibilities and limitations in the Pyrenean kingdom, finding out why the phenomenon took place. The different royal commissions given to the viceroys have also been analyzed to develop a better understanding of the legal support on which alienations were based. Finally, all the grants registered as sales, the identity of the buyers and the donations paid have been located. All this will allow us to have a more exhaustive vision of the complex process of venality in the kingdom of Navarre and a better understanding of the integration of the territory in the structures of the Monarchy.