Urban consolidation has transformed Australian cities. This transformation seems likely to continue, with consolidation embedded in current metropolitan plans. One justification of consolidation is that it eases unsustainable levels of household greenhouse emissions. Here, we review this claim, and find warning signs that 'actually existing' consolidation does not achieve this outcome. While there is a clear need for further research, action on unsustainable household consumption cannot wait for a definitive study. We outline an immediate policy response, focusing on the role of land-use planning.