Understanding the impact of the largest alliance of cities taking climate action

BRUSSELS, BELGIUM (June 24, 2026) – This year marks the 10th anniversary of the launch of the Global Covenant of Mayors for Climate & Energy (GCoM). To celebrate a decade of helping cities translate global climate commitments into local action, here are ten key facts highlighting the achievements of the world’s largest alliance for city climate leadership:

1. 14,000+ cities have joined GCoM since 2016, from across 150 countries, making it the largest alliance of cities taking action against the climate crisis. 
2. 1 in 7 people in the world live in a GCoM city.
3. 61% of the population represented by GCoM cities lives in the Global South where the most severe impacts of climate change threaten billions of people. 
4. In 10 years, GCoM has provided nearly $ USD 270 million in strategic and technical support to cities.
5. About 7,500 GCoM cities are equipped with a plan to tackle climate change, and all other GCoM cities are in the process of developing one. 
6. Collectively, GCoM cities are taking more than 220,000 actions to mitigate climate change, adapt to its impact, improve energy access and reduce energy poverty, creating at least USD $105 billion in investment opportunities which is three times more than 10 years ago. 
7. 450 million people globally live in a GCoM city taking action in response to a climate hazard. 
8. By 2050, GCoM cities could reduce emissions by 4.5 GtCO2e – equivalent to the emissions of India & Argentina.  
9. 83% of GCoM cities have set climate targets more ambitious than their national governments and 55% of GCoM cities are expected to achieve their climate targets faster than their national governments. 
10. 32 Mayors from around the world have shared their local experience and leadership to shape the global urban climate agenda by serving on the GCoM Board in the last 10 years.