The provisional resolution of the US East Coast dockers’ strike, which resulted in a pay offer last week of 62% over six years, is not expected to have an impact on global aluminium pricing.

However, one analyst claimed stockpiling by some companies “is contributing to a rise in prices.”

The dock workers protest had halted the loading and unloading of shipping containers, causing cargo-laden vessels to drop anchor and form long queues offshore, in the first strike by members of the dockworkers’ union, the International Longshoremen’s Association (ILA), since 1977 and came at a time when global shipping was already reeling from disruptions. 

Attacks by Iran-backed Houthi rebels in Yemen on commercial vessels on the Red Sea have further complicated shipping routes, making the Red Sea route increasingly dangerous and exacerbating the challenges facing the industry.

A decision on the offer is expected in January, subject to a voting process by union members.

The strike lasted three days, causing a minor backlog of shipments, which avoided a prolonged disruption that could have led to significant aluminium price hikes. The US relies heavily on imports from Canada, the Middle East, and India and, with its limited domestic smelting capacity, any disruption to port operations could have affected transaction prices.

Principal consultant Phil Hong at supply chain consultants Proxima warned: “Although the strike is currently paused, many companies are pre-emptively increasing their inventory by importing tinplate and aluminium rolls earlier, which is contributing to a rise in prices.”

For East Coast production, shipping materials from the West Coast and then transporting them back to the East Coast is not cost-effective, unless absolutely necessary to maintain supply chains, he said.

“If the agreement between the dockworkers and their employers is reached by mid-January, we can expect prices for tinplate and aluminium to stabilise, with a potential short-term reduction as companies begin using their stockpiled inventory. However, if the strike resumes, prices are likely to rise again due to the added complexities of importing and logistics challenges,” he said.

CRU Group senior analyst Matthew Abrams said: “It [the strike] happened at a time when demand was already starting to slow a bit and, with most metal still coming in through the West coast or over land, it just failed to impact the market at all.” 

But if the strike had continued it could have hit the canmaking market sector. Uday Patel, senior research manager at Wood Mackenzie said: “The US aluminium market is inherently short on supply, and any disruption would have quickly pushed the P1020 premium up by 30-40%. Fortunately, the quick resolution meant the impact was contained.”

The P1020 premium, which is added to the base London Metal Exchange (LME) price to reflect regional supply and demand conditions, could have surged in response to an extended strike. However, the timely agreement prevented a severe supply crunch that would have affected not only aluminium manufacturers but also industries including beverage can production.

Patel said the likelihood of an ongoing strike was low given the scale of the threat to the US as a whole, but he said: “If the strike had continued for any length of time, its effects could have been quite dramatic, with premiums easily rising 30-40%.”

For now, the market has responded with relief, as demand in the US remains relatively low due to ongoing weakness in key sectors like automotive and construction. Inventory levels had been built up slightly in anticipation of the strike, which helped cushion any immediate supply constraints. However, analysts remain vigilant, monitoring market dynamics and LME movements closely.

Although the strike’s resolution has temporarily stabilised the market, broader factors such as global supply chains, geopolitical developments, and potential LME interventions remain critical. “We are keeping a close eye on developments in the aluminium market, as any shifts in supply chain logistics could still cause fluctuations in the P1020 premium,” added Patel.

The focus will now be on whether the offer is accepted and if labour relations stabilise in the long term. The US is more dependent on aluminium imports compared with the more robust domestic production base for tinplate steel, which reduces its reliance on imports