The U.S. state with the largest coal reserves is Wyoming.

Wyoming holds the largest share of coal reserves in the United States, with the majority of the nation's coal deposits found in the Powder River Basin. This area is known for its vast, low-sulfur coal, which is in high demand for electricity generation. Wyoming's coal reserves are a critical resource for both domestic energy production and coal exports. The state's mines are among the largest in the world, contributing significantly to the U.S. coal industry and its role in global energy markets.