What are gasoline sulfur credits, and how do they work?

The U.S. Environmental Protection Agency’s (EPA) Gasoline Sulfur program sets limits on the sulfur content of gasoline sold in the United States, with the aim of reducing a variety of vehicle emissions. The program relies on tradable credits that allow U.S. refiners and gasoline importers to reach compliance with sulfur specifications. For the second year in a row, in 2023, gasoline suppliers obtained and retired more sulfur credits than they generated, a trend that could increase supplier compliance costs and the price of octane in gasoline if it continues.