A U.S. appeals court on Friday ruled that most of Donald Trump's tariffs are illegal, striking a blow to the Republican president's use of the levies as a key international economic policy tool.
The court allowed the tariffs to remain in place through October 14 to give the Trump administration time to file an appeal with the U.S. Supreme Court.
In response, Trump dismissed the ruling as "incorrect," insisting that his trade measures remain intact.
"ALL TARIFFS ARE STILL IN EFFECT! Today a Highly Partisan Appeals Court incorrectly said that our Tariffs should be removed, but they know the United States of America will win in the end," Trump said in a post on Truth Social.
Trump has made tariffs a pillar of U.S. foreign policy in his second term, using them to exert political pressure and renegotiate trade deals with countries that export goods to the United States. While the levies have given the administration leverage to extract concessions, they have also added volatility to global financial markets.
In its decision, the U.S. Court of Appeals for the Federal Circuit in Washington, D.C., said: "The statute bestows significant authority on the President to undertake a number of actions in response to a declared national emergency, but none of these actions explicitly include the power to impose tariffs, duties, or the like, or the power to tax."
The court addressed the legality of what Trump called "reciprocal" tariffs imposed in April as part of his trade war, as well as a separate set of tariffs from February against China, Canada, and Mexico. The decision does not affect tariffs issued under other legal authority, such as those on steel and aluminum imports.
Trump had justified both sets of tariffs under the International Emergency Economic Powers Act (IEEPA), a 1977 law that has historically been used to impose sanctions or freeze assets of foreign adversaries.
He was the first president to invoke the statute to levy tariffs.
The appeals court, however, said: "It seems unlikely that Congress intended, in enacting IEEPA, to depart from its past practice and grant the President unlimited authority to impose tariffs. The statute neither mentions tariffs (or any of its synonyms) nor has procedural safeguards that contain clear limits on the President’s power to impose tariffs."
Trump’s Department of Justice argued that the law allows tariffs under emergency provisions enabling a president to "regulate" imports or block them completely. Trump declared a national emergency in April over the long-standing U.S. trade deficit, saying it undermined American manufacturing and military readiness. He also argued the February tariffs were justified because China, Canada, and Mexico were not doing enough to curb illegal fentanyl shipments — a claim those countries denied.
The ruling came in response to two lawsuits: one brought by five small U.S. businesses and another by 12 Democratic-led states, which contended that only Congress has the constitutional authority to impose tariffs and that any delegation of that power must be explicit and limited.
The U.S. Court of International Trade had already ruled against Trump’s tariff policies on May 28, saying he exceeded his authority. Another Washington court also rejected Trump’s interpretation of IEEPA, and the government has appealed that case as well. At least eight lawsuits, including one by California, are challenging the legality of the tariffs.
The Treasury Department, the U.S. Trade Representative’s office, and the Commerce Department had no immediate comment on Friday’s ruling.