ABSTRACT Just transition policies are widely viewed as one of the most effective mechanisms for compensating and building support for decarbonization in fossil fuel communities. However, early empirical work suggests that many coal-producing regions remain opposed to decarbonization even when just transition policies are proposed or implemented. In this study, I add to and nuance existing accounts by analyzing data from 18 interviews with oil and gas workers and community members in the Canadian Oil Sands, the world’s third-largest fossil fuel reserve. I show how those living and working in the Oil Sands remain skeptical of renewable energy, optimistic about the long-term viability of fossil fuels, and strongly oppose the proposal for a just transition. These responses are patterned by feelings of fear, exclusion, and resentment towards the motives and actors driving decarbonization, which I argue demonstrates a threatened sense of ontological security. Reframing decarbonization and just transition policies as an issue of ontological security encourages scholars and policy makers to prioritize the social and emotional impacts of decarbonization and reconsider the conditions necessary for a just transition.