C40 Cities: When local action meets global ambition
Behind every climate solution is a community and a city that dared to lead.
Boston
Johannesburg
Chengdu
Stockholm
Karachi
Warsaw
Los Angeles
Hanoi
Bogotá
Chicago
Heidelberg
Nanjing
Wuhan
New York City
Lisbon
Sydney
Berlin
Lagos
Houston
Curitiba
Amman
Dalian
Salvador
Fuzhou
Casablanca
Tshwane
Tokyo
Ahmedabad
Nairobi
Barcelona
London
Oslo
Rome
Boston
Johannesburg
Chengdu
Stockholm
Karachi
Warsaw
Los Angeles
Hanoi
Bogotá
Chicago
Heidelberg
Nanjing
Wuhan
New York City
Lisbon
Sydney
Berlin
Lagos
Houston
Curitiba
Amman
Dalian
Salvador
Fuzhou
Casablanca
Tshwane
Tokyo
Ahmedabad
Nairobi
Barcelona
London
Oslo
Rome
Athens
Fortaleza
New Orleans
Washington, DC
Jakarta
Singapore
Bengaluru
Hangzhou
Quito
Durban (eThekwini)
Hong Kong
Guangzhou
Medellín
Freetown
Rotterdam
Buenos Aires
Yokohama
Mumbai
Amsterdam
Phoenix
Cape Town
Shanghai
Rio de Janeiro
Tel Aviv – Yafo
Guadalajara
Melbourne
Bangkok
Santiago
Seoul
Accra
Beijing
Copenhagen
Philadelphia
Athens
Fortaleza
New Orleans
Washington, DC
Jakarta
Singapore
Bengaluru
Hangzhou
Quito
Durban (eThekwini)
Hong Kong
Guangzhou
Medellín
Freetown
Rotterdam
Buenos Aires
Yokohama
Mumbai
Amsterdam
Phoenix
Cape Town
Shanghai
Rio de Janeiro
Tel Aviv – Yafo
Guadalajara
Melbourne
Bangkok
Santiago
Seoul
Accra
Beijing
Copenhagen
Philadelphia
Chennai
Paris
Istanbul
Dakar
Auckland
Milan
Mexico City
Dhaka (North & South)
Madrid
Delhi NCT
Toronto
Lima
Seattle
Kuala Lumpur
Ho Chi Minh City
Zhenjiang
São Paulo
Miami
Dubai
Abidjan
Qingdao
Ekurhuleni
San Francisco
Vancouver
Dar es Salaam
Quezon City
Shenzhen
Austin
Montréal
Addis Ababa
Portland
Chennai
Paris
Istanbul
Dakar
Auckland
Milan
Mexico City
Dhaka (North & South)
Madrid
Delhi NCT
Toronto
Lima
Seattle
Kuala Lumpur
Ho Chi Minh City
Zhenjiang
São Paulo
Miami
Dubai
Abidjan
Qingdao
Ekurhuleni
San Francisco
Vancouver
Dar es Salaam
Quezon City
Shenzhen
Austin
Montréal
Addis Ababa
Portland
C40 has
97
member cities
Making up more than
22%
of the global economy1
Accelerator Reports
Latest 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.
Latest News
July 23, 2025
Sources:
1. Oxford Economics data + C40 modelling and World Bank for global GDP.