This article focuses on the most relevant far right parties since the restoration of democracy in Spain, namely, Fuerza Nueva and VOX. These two parties show divergent electoral trajectories. While the former had some ephemeral prominence during the democratic process of transition, the latter emerged in 2018 and, for the time being, seems to have become established in several political arenas. Through an in-depth qualitative examination, this research explores the role of the organizational institutionalization process in the divergent electoral sustainability of both parties. The results show that it is possible to identify a temporal link, as well as certain mechanisms, between the way in which the parties develop organizationally and their electoral sustainability. In other words, a solid organizational institutionalization process has a positive effect on electoral sustainability. Overall, these findings suggest the need to further strengthen the so-called “internalist perspective” in the agenda of the far right, which entails a more systematic view of the characteristics of the parties themselves to explain their performance.