Top Aluminum Producer Adds Markups as Tariffs Upend Metal Market

Rio Tinto Group is imposing surcharges on aluminum shipments it sells to the US, a move that threatens to further disrupt a North American market already roiled by import tariffs that are driving up costs for consumers.

The Anglo-Australian mining giant is including the extra charge on aluminum orders delivered to the US citing low inventories, as demand starts to outstrip available supply, according to people with direct knowledge of the matter.

The US relies heavily on foreign aluminum supplies as it doesn’t have the capacity to produce enough to meet demand. Canada is its No. 1 foreign supplier, ...