The Main Carbon Registries: Verra, Gold Standard, ACR and CAR
Registries issue, track and retire carbon credits. Here is who runs the main ones and how to tell them apart.
What a registry does
A registry is the database where credits are issued, held, transferred and retired. Each credit gets a serial number, so it can be traced and cannot be counted twice. Registries also publish project pages, methodologies and issuance records, which is where buyers should start their checks.
Verra and the Verified Carbon Standard
Verra runs the Verified Carbon Standard, the largest voluntary carbon standard by number of credits issued. It covers forestry, agriculture, energy, cookstoves and many other project types through published methodologies, and its registry records each credit's status.
Gold Standard
The Gold Standard places particular emphasis on sustainable development co-benefits. Its projects must show how they contribute to the UN Sustainable Development Goals, and its registry lists project and issuance records publicly.
American Carbon Registry and Climate Action Reserve
The American Carbon Registry and the Climate Action Reserve operate mainly in North America. The Climate Action Reserve also runs compliance protocols for certain US programmes. Both publish methodologies and project records, and both are used for forestry and other land-based projects.
How to compare them
Registries differ in their methodologies, governance and the project types they cover, so comparing them means comparing the methodology behind the credit as well as the registry name. Check the project's registry page, its verification history and whether the credit has been retired.