The physical copper market is signaling a tightening supply environment, with London Metal Exchange (LME) spreads reaching their widest levels since the 2021 squeeze. The one-day spread has now hit $110, the highest since 2021, adding to a broader pattern of backwardation that is already reflected in the performance of copper-focused exchange-traded funds (ETFs), which have posted significant gains despite uneven capital flows.

Market structure tightens

The LME's front-month copper spread climbed to a $370 per ton premium, marking the widest one-month spread observed since the 2021 supply disruption, according to data highlighted by The Kobeissi Letter. The cash-to-three-month spread also widened to $434 per ton, indicating the substantial premium traders are paying for immediate delivery. The one-day spread reaching $110 underscores the acute near-term tightness in the exchange network.

This move into steep backwardation coincides with a prolonged drawdown in stockpiles. LME copper inventories have fallen for 42 consecutive days, the longest such streak since 2014. Total stockpiles now stand at 204,975 tons, with nearly half of the remaining metal already scheduled for withdrawal.

Physical tightness is further exacerbated by arbitrage flows toward the United States. Expectations surrounding tariffs on refined copper are drawing metal away from the LME system, reducing immediately available supply in the exchange network.

The key spread metrics are summarised below:

ETF performance vs. flows

Copper-related ETFs have rallied sharply over the past 30 days, though investor capital remains concentrated in larger funds.

The Sprott Junior Copper Miners ETF (COPJ) provides concentrated exposure to smaller producers and explorers, offering higher sensitivity to price changes. The USCF Daily Target 2X Copper Index ETF (CPXR) offers leveraged exposure to copper futures, presenting a higher-risk vehicle for short-term directional bets.

What the numbers show

A divergence exists between price performance and capital inflows. While COPP, COPJ, and CPXR have rallied significantly, they have not attracted massive new inflows. In contrast, the Global X Copper Miners ETF (COPX) has drawn roughly $2.5 billion in net inflows, bringing its assets to almost $8 billion. By comparison, COPP, COPJ, and CPXR have not reached $200 million in assets.

This pattern suggests that returns in smaller copper ETFs are driven by underlying asset appreciation rather than new capital creation. The broader ETF market reflects this concentration trend, with U.S.-listed ETFs attracting $191.3 billion in July, pushing inflows toward $1.3 trillion. Broad-market equity funds like VOO, SPY, and SPYM remained the largest beneficiaries of July's $75 billion in U.S. equity ETF inflows.

The current market structure indicates that copper prices and mining stocks are leading the move, while ETF flows remain focused on established, liquid products. COPX remains the primary destination for equity-side exposure, while CPXR serves traders seeking leveraged outcomes.

Copper prices have surged to new all-time highs in New York as traders accelerate shipments amid fears of impending import tariffs. The COMEX contract for September delivery closed at $6.7180 per pound, while the London market moved above $14,000 a ton. The spread between the two markets remains above $300, highlighting the magnet effect of the U.S. market on global flows.

The price rally is driven by uncertainty over U.S. trade policy. The Commerce Department missed a June deadline to recommend whether to impose phased duties on refined copper imports. These duties could begin at 15% in 2027 and rise to 30% in 2028. Despite the missed deadline, traders have acted on the prospect, with more than 200,000 tons arriving at U.S. ports in July, according to Bloomberg.

Supply Constraints Tighten Market

Supply disruptions are compounding the demand surge. The closure of the Strait of Hormuz cut seaborne sulfur shipments from the Gulf, while China’s export ban further restricted access. Together, these disruptions have removed roughly a quarter of global acid supply. This shortage cripples the solvent extraction-electrowinning (SX-EW) process, which accounts for more than 15% of world copper output. Operations in Chile and the Democratic Republic of Congo face increasingly tight inventory positions.

Chilean state producer Codelco has added to concerns by pausing the Andes Norte expansion at El Teniente following seismic findings. These operational halts reduce near-term output expectations from one of the world’s largest producers.

China’s Refining Dominance

The market dynamics highlight a strategic imbalance in global processing capacity. China mines only about 8% of global copper but controls about 60% of smelting and refining capacity. Phillip Mackey, a Canadian Mining Hall of Fame alumnus, noted that China produces about 12 to 13 million tons of refined metal annually. "We’re mining the copper and then shipping it to China to be smelted and refined and then bringing it back," Mackey told The Northern Miner. "It doesn’t make sense in the long term."

Mackey attributed China’s advantage to state-backed financing and industrial scale built over 25 years. In contrast, the U.S. smelting fleet shrank from about 12 facilities to two due to high capital costs and environmental permitting challenges.

Glencore Reports Strong Growth

Glencore Plc is capitalizing on these conditions with strong financial performance. The firm reported an 86% increase in adjusted EBITDA to $10.1 billion for the half-year period. Copper output rose by 15%, supporting the company’s target of reaching 1 million tons of annualized copper production by the end of 2028. Glencore is also pursuing a secondary listing on the Australian Stock Exchange (ASX) in October to access Australia’s pension market.

What the Numbers Show

The divergence between mining and refining capacity creates a structural vulnerability for Western markets. While copper prices rise, the lack of domestic smelting infrastructure in the U.S. means that even mined metal often relies on foreign processing. This dependency, combined with supply shocks in sulfur and acid, suggests that price volatility may persist until domestic processing capacity expands or trade policies stabilize.