About the Compact of Mayors

The Compact of Mayors is the world’s largest cooperative effort among mayors and city officials to reduce greenhouse gas emissions, track progress, and prepare for the impacts of climate change.

The Compact of Mayors will drive more aggressive city climate actions and reaffirm existing targets while capturing the significance of these efforts through a consistent, transparent public reporting of cities’ climate data. The data collected through the Compact of Mayors will become the evidence base we need to quantify the greenhouse gas impact of city action with the aim of:

·  Showing national governments the extent of action cities are already undertaking, so that it might be incorporated into national level strategies or further supported through more enabling policy environments and resourcing approaches

·  Encouraging increased capital flows into cities to support local action

·  Demonstrating the commitment of city governments to contribute positively towards more ambitious, transparent, and credible national climate targets by voluntarily agreeing to meet standards similar to those followed by national governments

·  Establishing a consistent and transparent accountability framework that can be used by national governments, private investors or the public to ensure that we can be held responsible or our commitments

In accordance with C40 membership standards, C40 cities will continue to report to CDP. CDP has added an additional Compact of Mayors module to their questionnaire to capture all the data cities need to demonstrate compliance. CDP will then share this data with the carbonn Climate Registry, the designated central repository for the Compact of Mayors, which will enable the compilation of data through existing national, regional, and global city reporting platforms. This mitigates the need for a city to report its climate data more than once.

To ensure a consistent and transparent way to measure emissions which conforms with IPCC national guidelines, the Compact of Mayors will use the Global Protocol for Community-Scale Greenhouse Gas Emissions Inventories (GPC) -- the world’s most widely-endorsed GHG accounting and reporting standard for cities.  For climate risks and adaptation data, a new framework is currently being developed.


C40 Cities & The Compact of Mayors


Learn More

• View the Compact of Mayors FAQ

• Visit the Compact of Mayors website

• Visit the Compact of Mayors on Medium

• Download the Compact