This page last reviewed September 7, 2018


The cap-and-trade regulation includes general requirements for linking to other trading programs.  To enable the mutual acceptance of compliance instruments from another emissions trading program, California must initiate a public process to amend the cap-and-trade regulation.  Linkage allows for the use of compliance instruments from an external greenhouse gas emission trading system to meet compliance obligations pursuant to the California Cap-and-Trade Regulation, and the reciprocal approval of compliance instruments issued by California to meet compliance obligations in the external trading program.  Any staff recommended amendments for Board consideration will go through a full rulemaking process as required under the Administrative Procedure Act.

General Linkage Information 

September 2018 Update: Linkage with Ontario Cap-and-Trade Program

On July 3, 2018, the Ontario government published a regulation (386/18) revoking Ontario’s cap-and-trade regulation (144/16), and suspended all Ontario entity CITSS accounts.  With Ontario’s departure from the linked carbon market, California and Québec are working together to ensure that the environmental integrity and stringency of our cap-and-trade program and market is maintained.  Our goals are to make certain that the program continues to reduce emissions of climate-changing gases as a crucial part of our efforts to combat the existential threat of climate change, while also continuing the smooth operation and integrity of our joint carbon market.

Please note that all compliance instruments in accounts registered in California or Québec are valid for compliance purposes and for trading or selling between participants of the two jurisdictions.

As new information becomes available, we will issue additional notices with as much detail and advance notice as possible to ensure all market participants receive the information at the same time.

Linkage with Ontario Cap-and-Trade Program

Linkage with Québec Cap-and-Trade System

Linkage Readiness Report

On November 1, 2013, Chair Nichols sent a letter to Governor Edmund G. Brown Jr. (Governor) with a linkage readiness report.  The report is in response to the Governor’s request in his letter provided to ARB on April 8, 2013.  Links to the transmittal letter and report are provided below.

On October 1, 2013, ARB and the Government of Québec announced the completion of an agreement that defines the process for working collaboratively and jointly to harmonize and integrate the California and Québec cap-and-trade programs.  This agreement fulfills the direction in Board Resolution 13-7 to document the coordination process in a written agreement.

  • California-Québec Agreement to Integrate and Harmonize their Cap-and-Trade Programs (English) (French

On May 9, 2012, ARB staff noticed amendments to the Board to effect linkage between the California and Québec Cap-and-Trade Programs.  Subsequent to the notice, Senate Bill 1018 was enacted requiring state agencies to notify the Governor that the agency intends to take such action to link with another greenhouse gas emissions trading program, and the Governor must make specified findings prior to the agency taking action to approve the linkage.

On February 22, 2013, ARB’s Executive Officer sent a letter to Governor Edmund G. Brown Jr. (Governor).  The letter requests that the Governor consider and make four findings that are necessary before the ARB can adopt a regulation that would link the greenhouse gas emissions trading programs developed in parallel by California and the Province of Québec.  Links to the letter and attachments are provided below.

Governor Brown's Response to ARB Pursuant to SB 1018:

ARB Request to Governor Brown Pursuant to SB 1018:


For questions or comments, please contact Jason Gray at (916) 324-3507