The issue of fracking highlights the variability of trade union approaches to the environment in the UK energy sector, as reflected in their narratives and strategic organising orientations. Stories alone cannot change the material interests underlying complex societal conflicts, yet transformative policies on the climate crisis cannot emerge without a coherent story about the environmental crises and possible solutions. This article uses unions’ positions on fracking as a proxy for opposing/supporting/hedging against climate action to see how divergent positions amongst the UK’s three biggest unions in the energy sector (UNISON, Unite and GMB) and the TUC are reinforced or challenged by internal union narratives and strategic foci. Drawing on four in-depth expert interviews and 148 union documents, the main union narratives and strategies are analysed and clustered. The article’s key insight is that unions’ specific narratives differ depending on a union’s orientation. Pro-fracking unions address the short-term immediate financial and material concerns of members and hence promote business partnerships, while anti-fracking unions develop broad-based grass-roots alliances to address the climate crisis. The key entry point for transformative coalitions lies in promoting a coherent and positive narrative about transformative change, in line with scientific evidence.