The California Air Resources Board (CARB) has announced a significant implementation update for California's Climate Corporate Data Accountability Act (SB 253), proposing to extend the deadline for the first greenhouse gas emissions disclosures required under the law.

Under the updated proposal, companies subject to SB 253 would be required to submit their first Scope 1 and Scope 2 greenhouse gas emissions reports by November 10, 2026, replacing the previously established August 10, 2026 reporting deadline. The extension would provide reporting entities with an additional three months to prepare emissions inventories, validate data, and establish internal reporting processes as California moves toward implementation of one of the most comprehensive corporate climate disclosure regimes in the United States.

CARB stated that the proposed deadline extension is intended to facilitate a smoother transition into the program's first reporting cycle and provide regulated entities with additional time to comply with the state's reporting requirements. The agency also continues to develop guidance, reporting mechanisms, and administrative procedures necessary for implementation.

Although the proposed extension provides additional preparation time, CARB's announcement reinforces the agency's commitment to implementing the law. Companies that may be in scope should continue developing greenhouse gas inventories, assessing organizational boundaries, evaluating data collection processes, and preparing governance frameworks necessary to support future reporting obligations.

The proposed shift from August 10 to November 10, 2026 represents the most significant implementation update to date and provides organizations with additional flexibility as they prepare for California's inaugural corporate greenhouse gas reporting cycle.