Cities around the world are facilitating ambitious and inclusive action on climate change by adopting participatory and collaborative planning approaches. However, given the major political, spatial, and scalar interdependencies involved, the extent to which these planning tools equip cities to realise 1.5 °C climate change scenarios is unclear. This article draws upon emerging knowledge in the fields of urban planning and urban climate governance to explore complementary insights into how cities can pursue ambitious and inclusive climate action to realise 1.5 °C climate change scenarios. We observe that urban planning scholarship is often under-appreciated in urban climate governance research, while conversely, promising urban planning tools and approaches can be limited by the contested realities of urban climate governance. By thematically reviewing diverse examples of urban climate action across the globe, we identify three key categories of planning dilemmas: institutional heterogeneity, scalar mismatch, and equity and justice concerns. We argue that lessons from urban planning and urban climate governance scholarship should be integrated to better understand how cities can realise 1.5 °C climate change scenarios in practice.