California's SB 253 Climate Disclosure Rules: What You Need to Know

Summary Senate Bill 253 requires companies with revenue above USD 1 billion that do business in California to disclose Scope 1, 2 and 3 emissions annually to CARB, measured under the Greenhouse Gas Protocol and covered by third-party assurance. The first Scope 1 and 2 reports are due on 10 November 2026, with Scope 3 reporting starting in 2027 on the schedule CARB sets in its second rulemaking. Scope is set by revenue and California presence, so the law covers public and private companies headquartered in any state, with exemptions for non-profits, insurers regulated by the California Departme