International humanitarian non-governmental organizations play a crucial role in the early response to some of the most catastrophic effects of climate change on nature, humans, societies and states. However, there is limited knowledge about how these organizations perceive and subsequently respond to climate change and its implications for security. To address this gap, this article provides a comprehensive account of how international humanitarian non-governmental organizations conceptualize climate change and its associated risks. Methodologically, the study employs a content analysis of publications from six influential organizations between 2016 and 2022. Theoretically, it adopts a framework for analyzing climate security discourses. The article finds that the examined organizations acknowledge climate change as a critical issue, but they focus on different aspects of it. Notably, their conceptualizations of climate change and related risks are based on diverse security logics and carry significant implications for their humanitarian notions and practices more generally.