Final disposal of spent nuclear fuel (SNF) from nuclear power plants (NPPs) is an ethical issue with implications within and across generations. We address this issue from the perspective of nuclear communities that host nuclear waste disposal sites. These are primarily the communities that face injustice due to the potential radiological risks. A resident survey (n = 454) was conducted in two Finnish nuclear communities, i.e. Eurajoki and Pyhäjoki, that are being considered as alternative sites for a second repository for SNF. The nuclear waste management (NWM) company Posiva is already building a repository in Eurajoki, the first in Finland. These communities are in different stages of their lifecycles as nuclear communities. We investigated the residents’ conceptions of justice and trust regarding the repository SNF management and its main actors, and how these conceptions related to acceptance of the repository. The main findings show that residents of both communities perceived intragenerational and intergenerational injustices to be important in the procedures and the distribution of risks and benefits of the proposed repository. Claims regarding justice and trust were related to the acceptance of the repository. The community with the longer history with NWM expressed greater mistrust and perceived greater procedural injustice than the community with less earlier experience, which–in turn–expressed more concern over intragenerational distributive justice than the former community. Moreover, having longer history with NWM did not lead to a different understanding regarding responsibility toward future generations as resident’s in both communities expressed similar concern over intergenerational justice. Moreover, having more experience of NWM did not enhance local acceptance. We emphasize that these results should be understood in the light of the prevailing situation in Finland, where the planning of the second repository is at a very early stage.