A substantial number of people across the globe deny and minimize the role of human action in climate change, which can inhibit mitigation efforts. Climate communication research shows that scientific-consensus communication is a promising intervention to tackle climate denial, yet most research investigating this strategy was conducted in the Global North. In the current preregistered research, data from a large, global collaboration (63 countries, N = 10,390) demonstrate that exposure to one simple climate consensus message has a meaningful effect on the estimate of consensus among climate scientists (d = ∼0.40). Both in the Global North and in the Global South the consensus message increased consensus estimates, but this effect was larger in the North than in the South. The effect of the consensus message on belief in human-caused climate change was statistically significant but small (d = ∼0.07) and similar between global regions. This demonstrates that short and scalable consensus messages can be part of communicators’ toolkit to address climate denial across the globe, but also that repeated and/or additional communication may be required to boost its effects.