The Trump administration doubled steel and aluminum tariffs to 50 percent effective June 4, an action likely to cause ripple effects throughout automotive supply chains also impacted by vehicle and parts duties.

The move, which applies to imports of steel and aluminum from all countries except the U.K., is part of a bid by President Donald Trump to boost the domestic steel and aluminum sectors. But it is also poised to increase costs for U.S. manufacturers, including vehicle and parts manufacturers, that rely on metals purchases.

Here, Automotive News explains what the latest developments on steel and aluminum tariffs mean for the auto industry.

The 50 percent tariffs apply to all steel and aluminum imported to the U.S., except for British metals, which are subject to a 25 percent duty while the U.S. and U.K. iron out the details of a trade agreement they agreed to in principle on May 8.

The duties also apply to a wide range of derivative products comprised of foreign steel or aluminum, including certain parts used in automotive products. About $150 billion in goods are subject to the steel and aluminum derivative products, including $25.7 billion in aluminum car, truck, bus and tractor parts.

Are there any auto exceptions to steel and aluminum tariffs?

Yes. After weeks of lobbying by automakers and suppliers, the Trump administration in April provided two forms of tariff relief to the auto industry.

One measure “destacks” auto tariffs from many other duties the Trump administration has imposed, including those on steel and aluminum. That means if a vehicle or part is subject to the 25 percent auto tariff, importers would only have to pay that and would not be required to pay any steel and aluminum duties on top of it.

The relief was welcomed by the auto industry, especially suppliers that raised alarms about the stacking nature of the Trump administration’s tariffs. But the relief only applies to vehicles and parts explicitly called out by the Trump administration as being subject to the auto tariff.

Parts that are not on the auto tariff list but are on the steel and aluminum derivative lists are subject to the metals duties, as well as 10 percent tariffs on most U.S. trading partners. But those parts would not be subject to tariffs the Trump administration has placed on imports from Canada and Mexico, according to Trump’s June 3 presidential proclamation.

Click here for a list of parts that fall under the auto tariff.

Are steel and aluminum tariffs impacted by recent court decisions?

No. The U.S. Court of International Trade ruled on May 28 that the reciprocal tariffs Trump placed on U.S. trading partners in April as well as tariffs placed on Canada, Mexico and China in response to fentanyl trafficking are illegal because the president overstepped his authority under the 1977 International Emergency Economic Powers Act. An appeals court paused the Court of International Trade ruling while it considers the case.

The sectoral tariffs Trump implemented are not affected because they were put into place under a different law. Those tariffs, including duties on steel, aluminum and autos, fall under section 232 of the Trade Expansion Act of 1962.

How might steel and aluminum tariffs impact the auto industry and the U.S. economy?

The tariffs follow those Trump put into place in 2018 during his first term, when steel imports were subject to a 25 percent duty and aluminum importers had to pay a 10 percent tax.

A 2023 report by the U.S. International Trade Commission found that the tariffs reduced imports of affected steel by 24 percent while raising prices for steel products by 2.4 percent. Aluminum imports fell 31 percent, while prices rose 1.6 percent.

The report found that while domestic steel and aluminum producers benefited from the tariffs, auto manufacturers reported decreased metals supply, higher input costs and longer lead times.

Over time, the Trump and Biden administrations reached deals with major U.S. trading partners that either lifted those 2018 tariffs or put into place import quotas, making steel and aluminum duties less of a factor for businesses to consider until Trump ended those agreements in March.

Where does the U.S. import steel and aluminum from?

The U.S. imported about $31.5 billion of steel and $18.5 billion of aluminum in 2024, according to a report by the Congressional Research Service.

Canada was the largest source of both materials brought into the country, accounting for 23 percent of imports of steel and about half of aluminum imports.

Other major sources of steel include Mexico, the European Union, Brazil, South Korea and Japan. Other aluminum sources include the EU, the United Arab Emirates, China, South Korea and Bahrain.

Most U.S. steel consumers source the metal domestically. Imports accounted for 23 percent of all finished steel in the U.S. in 2024, according to an estimate by the American Iron and Steel Institute. The U.S. is dependent on imports for about half of its aluminum.