Copper at $14,000: How US Tariff Arbitrage Broke the Global Market

What Is Driving Copper Prices Toward $14,000?

Mine supply disruptions. Freeport-McMoRan's Grasberg force majeure removed roughly 525,000 tonnes of supply across 2025–2026, flipping a projected global surplus into a deficit almost overnight . Additional disruptions at other major mines and a concentrate shortage at smelters have compounded the deficit .

Fundamentals vs. speculation. Fund managers have re-entered copper on the long side, adding financial momentum to what was already a tight physical narrative . However, analysts at J.P. Morgan, S&P Global, and Goldman Sachs have cautioned that prices are "overextended" relative to actual demand, with Goldman forecasting a pullback later in 2026 .

Macro and geopolitical tailwinds. Growing demand from AI data centers, power grids, and EVs underpins the long-term bull case, while the US-led conflict in the Middle East has disrupted key shipping lanes, tightening delivered supply .

Record US Imports and the Comex-LME Arbitrage

The Comex-LME price spread has been the single most disruptive force in global copper flows.

US imports surged 80% in 2025 to a record 1.64 million metric tons, as traders capitalized on a wide arbitrage window created by the expectation of refined copper tariffs . The pace of arrivals accelerated further in 2026, though the premium has narrowed at times when tariff clarity was delayed .

Comex inventories hit a record 652,200 tonnes (up from roughly 80,000 tonnes in February 2025), while LME and SHFE stocks outside the US have been drained . By end-June 2026, more than half of all visible refined copper sat in the US market .

The arbitrage reopens periodically. The Comex premium over LME widened back above $500/ton in late May 2026 on renewed tariff speculation, then collapsed when the White House delayed decisions, only to re-widen again .

Global Inventories and Backwardation: Pricing Scarcity at a Time of Plenty

The market is experiencing a paradoxical situation.

Global exchange inventories (LME + Comex + SHFE) surpassed 1.1 million tonnes in early 2026 — the highest since 2003 — and neared 1.2 million tonnes by mid-2026 . This is not a genuine global shortage; it is a geographic misallocation driven by tariff arbitrage.

Non-US stocks are being drained. While Comex stocks swell, LME and SHFE inventories outside the US have been drawn down sharply, creating localized tightness that supports backwardation (near-term premium) in those contracts .

Reuters described the dynamic as "pricing scarcity at a time of plenty" — the LME price reflects the fear of where metal isn't (outside the US) rather than overall availability .

Status of the Trump Administration's Refined Copper Tariff Decision

The tariff regime has already been partially implemented in stages, with a phased universal tariff on refined copper now scheduled.

• July 30, 2025 (effective August 1, 2025): President Trump imposed 50% Section 232 tariffs on semi-finished copper products (pipes, wires, rods, sheets) and copper-intensive derivative products, but explicitly excluded refined copper (cathodes) at that stage .

• April 2, 2026 (effective April 6, 2026): A second proclamation modified the regime, imposing a flat 50% tariff on most copper articles and introducing a phased universal tariff on refined copper — 15% starting in 2027 rising to 30% in 2028 — as recommended by the Secretary of Commerce .

• June 1, 2026: A further proclamation adjusted the tariff structure again, confirming the phased refined-copper tariff path and tightening rules of origin and derivative coverage .

• Current status (as of late July 2026): The key "pending" decision on refined copper is no longer whether tariffs will come, but when and at what rate. The 2027 start for the 15% refined-copper tariff appears locked in, though some market participants had speculated the administration could accelerate or delay it .

Potential Market Outcomes: Tariffs Imposed vs. Shelved

If refined copper tariffs are imposed (base case: 15% in 2027, 30% in 2028)

• Comex premium persists or widens. US buyers would face a structural cost advantage for domestic metal, keeping Comex at a sustained premium over LME .
• US inventories remain high; rest-of-world tightens further. The incentive to ship metal to the US continues, draining LME and SHFE stocks and reinforcing backwardation in non-US contracts .
• Price support near term, correction later. Goldman Sachs has forecast that tariff clarity in mid-2026 would cause prices to decline from record highs later in the year as speculative froth is removed, but the tariff itself provides a floor for US prices .
• Structural market split. Reuters has warned the dislocation "risks becoming a structural split" between the US and international copper markets, with lasting divergence in pricing and inventory allocation .

If refined copper tariffs are shelved or significantly delayed

• Comex premium collapses. The arbitrage window would shut rapidly, causing a sharp devaluation of metal already in transit or stored in US warehouses .
• Massive inventory rebalancing. US copper inventories would unwind as metal is re-exported or discounted, flooding the global market and putting severe downward pressure on LME prices .
• Sharp price correction. Goldman Sachs and other analysts expect LME prices to fall well below $12,000/ton if tariffs are shelved, as the "tariff premium" embedded in current prices evaporates .
• Temporary glut; demand fundamentals reassert. Without the tariff distortion, the market would revert to focusing on genuine supply deficits (mine disruptions) and demand growth (AI, electrification), which are supportive but at significantly lower price levels .