Peabody Energy has completed a pilot shipment of Powder River Basin coal from Wyoming to Vietnam using a cross-border route through Mexico, a move the company and its rail partners say could open another Pacific export channel for U.S. thermal coal.

The coal began its journey at Peabody's North Antelope Rochelle Mine in Wyoming's Powder River Basin, local media reported. Union Pacific carried it by rail to Nogales, Arizona, where Ferromex took over for the Mexican railroad through Sonora. The cargo then reached the Port of Guaymas on Mexico's Gulf of California coast, was loaded onto a vessel and sailed across the Pacific to Vietnam.

Union Pacific said more than one test train has already reached Guaymas. The railroad and its partners are now reviewing whether additional shipments make sense. The pilot's purpose is to assess whether the route can offer another viable export channel for Powder River Basin coal.

Peabody President and CEO Jim Grech said the effort demonstrates the company's capacity to link the Western Hemisphere's biggest coal basin with the world's largest center of thermal coal import demand, along with help from U.S. and Mexican government officials, port authorities and logistics partners.

The company said the Mexican port can handle more coal if market conditions make future exports economically attractive. The first cargo used a Panamax-sized vessel loaded in early June, and the company said it arrived at its Asian customer on schedule and met specifications. Peabody added that the shipment has drawn interest from other Asian buyers and that it is considering a second Guaymas test.

Peabody does not view Vietnam as a one-off destination. Company presentations name Japan, South Korea, China's Taiwan, the Philippines and Vietnam as possible markets that could be served through expanded West Coast export routes.

Asia accounts for more than 80% of seaborne thermal coal imports worldwide, Peabody said, making Pacific export infrastructure strategically valuable to a Powder River Basin producer pursuing more overseas customers. The company also believes seaborne access could help improve margins when international coal prices are high enough to cover the extra transportation cost.

North Antelope Rochelle gives Peabody the scale to chase those markets. The surface mine is the largest coal mine in the U.S. and produced roughly 65 million short tons in 2025, served by both Union Pacific and BNSF Railway.

Vietnam's role in the test is notable because the country has shifted from exporting coal to importing it as electricity demand and coal-fired generation capacity have grown. U.S. Energy Information Administration data showed Vietnam became a net coal importer in 2015, when domestic consumption exceeded supply.

U.S. coal sales to Vietnam have traditionally been a small share of American exports, but recent figures indicate a commercial market exists. U.S. coal exports to Vietnam increased by nearly five times year on year to 704,000 tonnes last year, accounting for 0.84% of the country's total exports, higher than 0.15% a year ago, the country's Census Bureau data showed. Thermal coal offtakes to Vietnam reached 299,000 tonnes, up 105.35% on the year.

The broader U.S. coal export picture has weakened. Total exports dropped to about 84.0 million tonnes in 2025 from 98.27 million tonnes in 2024, official data showed. Thermal coal exports fell 17.89%, and coking coal exports declined 11.43%. That backdrop makes new customers and export corridors more important for producers trying to diversify beyond domestic utilities.

Wyoming Governor Mark Gordon has long made international market access for the state's coal a priority. According to his office, Gordon has backed legal challenges to federal rules affecting coal-fired generation and opposed federal restrictions on coal leasing in the Powder River Basin.

Guaymas is not Peabody's only attempt to gain additional Pacific access. The company is also exploring exports through a proposed terminal at the Port of Oakland in California, which Peabody has said could start operating in late 2028. Its latest investor materials list Guaymas and Oakland as possible West Coast export channels and say Peabody is weighing a second Guaymas shipment while continuing to work on Oakland.

For the Guaymas corridor, whether the route becomes a major long-term export channel will hinge on coal prices, rail and port costs, Asian demand and competition from other suppliers.