Published online: May 2025 This paper outlines the impact of rising military expenditure on the achievement of Sustainable Development Goal 13: take urgent action to combat climate change and its impacts, looking specifically at the following targets: Strengthen resilience and adaptive capacity to climate-related hazards and natural disasters in all countries; Integrate climate change measures into national policies, strategies and planning; Implement the commitment undertaken by developed-country parties to the United Nations Framework Convention on Climate Change to a goal of mobilizing jointly $100 billion annually; Promote mechanisms for raising capacity for effective climate change-related planning and management in least developed countries and small island developing States, including focusing on women, youth and local and marginalized communities. Through reviewing a range of research and presenting this alongside the historical and present context of military expenditure, this analysis finds that the global increase in military expenditure poses a substantial risk to the achievement of SDG 13.