U.S. proved reserves of crude oil and lease condensate totaled 46 billion barrels at year-end 2023, a 4% decline from the previous year’s record, according to our U.S. Crude Oil and Natural Gas Proved Reserves, Year-End 2023 report. U.S. proved reserves of natural gas fell to 604 trillion cubic feet, a 13% decline from their 2022 record. Both declines marked the first annual decrease in U.S. proved reserves for those fuels since 2020.