Cities are driving forward climate solutions through collaboration
As extreme weather and pollution intensify, they increase existing inequalities and make cities less livable. Cities are working together through the C40 Accelerators to take rapid climate action and protect their communities. Since 2017, 89 C40 cities, home to 380 million people, have committed to these initiatives. They aim to halve emissions by 2030, increase climate resilience, and ensure that fairness guides every action.
Accelerators in action
C40 Accelerators help cities adopt effective climate solutions in key sectors. They enable mayors to deliver cleaner air, create thousands of green jobs, and have helped mobilise over USD 42 billion of investment into clean sectors to date.
C40 helps cities work towards ambitious targets with specific milestones. This creates a network for sharing successful strategies and scaling effective solutions.
Turning climate commitments into real-world results
Signatory cities are exceeding goals and setting the stage for even more action:
Air quality improvements
94 million more residents in C40 cities breathe cleaner air, with a 5% average air quality boost from 2018 to 2021.
Clean transportation progress
82% of signatory cities have adopted measures to promote electrified transport. 50% have restricted high-polluting vehicles in major areas.
Sustainable finance mobilisation
Over USD 500 billion in city and pension fund assets are now fossil fuel-free investments. Additionally, USD 84 billion in municipal assets have been divested from fossil fuels.
Zero-emission building standards
70% of signatory cities have set energy regulations for buildings, aiming for net-zero carbon by 2030. Meanwhile, 78% run retrofit programmes for existing buildings.
Waste reduction success
All signatories of the C40 Towards Zero Waste Accelerator have banned single-use materials. Also, 76% have city-wide systems for segregating recycling and organic waste.
Green jobs creation
Climate projects are creating jobs for residents. Freetown’s tree planting initiative alone employed over 1,000 people directly, with another 2,500 jobs created in supporting industries.
Urban nature expansion
Most cities (62%) now run tree planting and nature restoration programmes that involve local residents. Several cities have reached their targets of making 30-40% of urban surfaces green or water-permeable.
Our Accelerators
See the cities driving real climate progress, from cleaner air and green jobs to sustainable investment and renewable energy.
Learn about the ambitious targets cities have set for reducing air pollution and protecting public health.
See how cities are pioneering zero-emission building sites and setting new standards for sustainable construction.
Explore city strategies for fossil fuel divestment and scale up investments in the green economy.
See how C40 cities are protecting residents from extreme heat through cooling strategies and climate adaptation plans.
Learn about city commitments to zero-emission transport and walkable streets that prioritise people over cars.
Discover the ambitious building standards and retrofit programmes cities are implementing for net-zero carbon.
Learn about cities’ switch to clean energy and cutting ties with fossil fuel suppliers through ambitious renewable energy programmes.
Find out how cities are improving waste management and methane reduction through targeted action.
See how cities in Africa, Asia, and Latin America are ensuring healthy meals for every child, modernising markets, and supporting local food businesses.
Learn about the circular economy targets and waste diversion strategies that cities are implementing globally.
Discover nature-based solutions and urban resilience commitments cities are making to tackle climate risks.
Learn how the C40 and UN-Habitat partnership supports cities to adopt compact, connected, and climate-responsive planning.
Explore climate adaptation strategies and water system targets that cities are setting for flood protection.
Frequently asked questions
What’s the difference between C40 Accelerators and other climate programmes?
C40 Accelerators are science-based political commitment frameworks with specific targets and timelines, not just voluntary initiatives. Cities make public commitments with measurable goals and report on progress regularly. This accountability structure helps cities achieve faster, more substantial results than traditional climate commitments.
How do cities choose which Accelerators to join?
Cities typically select Accelerators based on emission sources, policy priorities, and implementation capacity. For example, cities with high transport emissions often join Green and Healthy Streets, while those focused on energy transition choose Renewable Energy. Cities can participate in multiple Accelerators simultaneously.
What support do cities receive after joining an Accelerator?
Participating cities get access to peer learning networks, additional support from a dedicated Accelerator team, potential technical assistance, and regular progress tracking support. C40 connects cities facing similar challenges so they can share strategies and solutions. Cities also receive help with measuring progress and reporting results.
Are there costs associated with joining C40 Accelerators?
C40 membership and Accelerator participation are free for cities. However, cities are responsible for implementing the policies and projects needed to meet their Accelerator commitments. Many cities use innovative financing, partnerships, and grants to fund their climate actions.
How long does it take to see results from Accelerator commitments?
Some benefits appear quickly – air quality improvements from transport policies can be measurable within months. Longer-term targets like renewable energy transitions typically show significant progress within 2-3 years. Most Accelerators have milestone targets that allow cities to track and celebrate progress along the way.
Accelerator Reports
2023 Reports Now Available
Since 2017, 74 forward-thinking C40 cities have been driving transformative action in critical sectors through C40’s High-Impact Accelerators.
In the latest Accelerator Reports, we celebrate the progress and impact of cities’ climate actions.
