World Cities Day brings Urban October to an end on 31 October each year and was first celebrated in 2014. As with World Habitat Day, a global observance is held in a different city each year and the day focuses on a specific theme.

On 31 October 2026, the Global Observance of World Cities Day will be related to theme "Regenerating the City: Adequate Housing for All" and on the Award Ceremony for the Fourth Cycle of the Global Award for Sustainable Development in Cities (Shanghai Award). The theme focus is on addressing urban regeneration as a catalyst for achieving adequate housing for all. It will showcase how combining area-based regeneration with housing and informal settlements strategies can deliver inclusive climate-resilient neighborhoods, consistent with the principles of adequate housing for all. It will also emphasize participatory, community-led regeneration, supported by safeguards that prevent displacement and ensure benefits for existing residents through improved housing.