Trump tariff threat built a US copper mountain, but the effects are fading
XLB•Trump’s tariff threat helped lift US copper stocks to about 1.6 million tons, while the price gap that encouraged shipments has narrowed to about $310 a ton. A decision on potential tariffs remains unannounced.
1. Tariff threat drew copper
The prospect of US import tariffs helped push Comex-approved warehouses to hold roughly 70% of the world’s visible copper stocks, creating shortages elsewhere despite a global surplus. The Comex-LME price gap peaked above $3,000 a ton in July last year and has since fallen to about $310 a ton, weakening the incentive to ship more metal to the United States.
2. Tariff decision unresolved
The US Commerce Department was due to report on the domestic copper market by June 30, so President Donald Trump could decide whether to impose a 15% tariff on refined copper imports from January 1, 2027, rising to 30% in 2028. No decision has been announced. Macquarie analyst Alice Fox said one likely scenario is that the January deadline passes without a decision, leaving tariffs unresolved.
3. US stocks and surplus
Macquarie estimates that US copper stocks on and off exchange total about 1.6 million tons. Since the end of February last year, Comex stocks have climbed nearly 750% to more than 714,000 tons, while copper in LME warehouses in New Orleans and Baltimore has risen 44% since mid-August to nearly 130,000 tons. The United States imported more than 1.62 million tons of copper last year, up 80% from 2024, and US production was 1 million tons.
