On June 4, 2020, the U.S. Environmental Protection Agency (EPA) released a proposed rule for calculating costs and benefits from Clean Air Act rulemakings. The proposal would require EPA to undertake a cost-benefit analysis for all significant Clean Air Act rulemakings — that is, those estimated to have at least a $100 million impact on the economy or are otherwise deemed significant — using the “best available scientific information” and instituting other procedural requirements. The proposal contains areas of high priority for the administration and contention for environmental groups, such as prohibiting double-counting benefits from one rulemaking in another rulemaking. The proposed rule builds on the agency’s June 2018 advanced notice of proposed rulemaking and EPA Administrator Andrew Wheeler’s June 2019 policy memo on cost-benefit analysis. According to the proposal, additional cost-benefit analysis rulemakings should be expected under other federal pollution control laws.