The threat of U.S. tariffs on imported copper has triggered a massive stockpiling effort, pushing prices on the New York Commodity Exchange (Comex) to record highs. [3, 4] Traders are moving copper into American warehouses ahead of possible tariffs of 15% in 2027. [4] Those tariffs could rise to 30% by 2028. [4]
The rush has pushed U.S. copper inventories to unprecedented levels and created a significant price premium over the London Metal Exchange. [3, 12] Metal diverted to the United States has turned a projected global copper surplus in 2026 into a balanced or even deficit market for the rest of the world, tightening supply. [3, 4, 10] Recent labor strikes at major mines in Chile, the world's top copper producer, have added to the market tightness. [16, 18]