US president Donald Trump has imposed tariffs on the importation of copper, although initially steering clear of primary copper imports, which would increase manufacturing costs for US firms.

A 50% import duty is to be levied on semi-finished copper products, such as copper wire and tubes, and intensive copper derivative products, such as pipe fittings, cables, connectors and electrical components, from 1 August. The Commerce Secretary recommended  30% tariff on semi-finished copper products.

“The Secretary found that the present quantities of copper imports and the circumstances of global excess capacity for producing copper are weakening our economy, resulting in the persistent threat of further closures of domestic copper production facilities and the shrinking of our ability to meet national security production requirements,” said a White House proclamation by Trump.

“Copper is the second most widely used material by the Department of Defense and is a necessary input in a range of defense systems, including aircraft, ground vehicles, ships, submarines, missiles, and ammunition,” the proclamation continued.

The Secretary of Commerce reported the results of an investigation into the effects of imports of copper under section 232 of the Trade Expansion Act of 1962, which Trump ordered under Executive Order 14220 of February 25.

With Trump engaged in trade negotiations with China, the proclamation stopped short of naming the Asian nation in its comments about global copper smelting and refining, and unfair trade practices, limiting his comments to noting “that a single foreign country dominates global copper smelting and refining, controlling over 50% of capacity.”

The proclamation also noted that “overly burdensome environmental regulations” in the US, have “hollowed out US copper refining and smelting” and caused the nation to be overly reliant on foreign copper imports.

“I concur with the Secretary [of Commerce’s] finding that copper is being imported into the US in quantities and under circumstances that threaten to impair the national security of the US.  … I determine that it is necessary and appropriate to impose tariffs to adjust imports of copper and its derivatives so that such imports will not threaten to impair the national security of the US,” said the proclamation.

The US produces about half of its annual consumption, some 850,000t in 2024, mainly from Arizona. Its 800,000t of copper imports in 2024 came from Chile (35%), with which it enjoys a free trade agreement, Canada (26%), Peru (7%), Mexico (7%), and Democratic Republic of Congo (2%), according to the US Census Bureau.

The White House clarified that the copper 232 tariffs do not add to the auto 232 tariffs, and that if a product is subject to auto 232 tariffs, those tariffs apply and not the copper tariffs. It also stipulated that the import of copper input materials such as copper ores, concentrates, mattes, cathodes, anodes and scrap are not subject to 232 or reciprocal tariffs.

The president authorised the Secretary of Commerce to take steps under the Defense Production Act to support the domestic copper industry. This includes requiring 25% of high-quality copper scrap produced in the US to be sold in the US to improve access to this feedstock for domestic fabricators and secondary refiners.

To boost domestic refining capacity, it also stipulated that from 2027, 25% of copper input materials produced in the US must be sold in the US, increasing to 30% in 2028 and 40% in 2029. Low volumes of US copper scrap are currently recycled in the US, with the majority of it exported to China.

The Trump administration is looking to advance the development of domestic copper projects. The 40Blb Resolution copper project in Arizona, a joint venture between Rio Tinto and BHP, led the list of priority projects announced by the president in April. Also named to the list of FAST-41 process projects is Newrange Copper Nickel’s NorthMet in the Duluth Complex in Minnesota.