Tourism contributes to climate change through CO2 emissions, and stakeholders must work together to reduce the negative impact of the industry. Therefore, this study explores online travel discussions on Reddit to investigate consumers’ beliefs regarding self-efficacy and barriers to climate change mitigation. The study relies on combining machine learning and thematic analysis. The results show that the intersection of tourism and climate change fosters extensive online engagement, indicating that many users are aware that travel and climate change are connected. However, self-efficacy was low overall, or not manifested in users’ contributions. Further, at least 10 barriers to climate change mitigation were identified. Suggestions on how to overcome such barriers and increase efficacy beliefs are discussed, and directions for future research are given.