Copper Spread Becomes Tariff Risk Gauge as U.S. Copper Prices Near Record Highs

The spread between U.S. copper futures and London Metal Exchange prices is now being seen as an indicator of potential new tariffs on refined copper.

This shift comes as copper prices near record levels, with heavy inflows into the U.S. driven by a growing tariff premium and supply constraints.

Societe Generale estimates that the current COMEX-LME copper spread implies a 14.6% chance of a 15% U.S. tariff in January 2027 and a 37% chance of a 30% duty in January 2028.