ISSAQUAH, WA – Warehouse retailer Costco filed a lawsuit Tuesday seeking a full refund of the tariffs it has paid to the federal government if the U.S. Supreme Court invalidates President Donald Trump’s import taxes.
Costco operates 918 membership warehouses, including 632 in the U.S. and Puerto Rico. It also operates e-commerce sites in the U.S. and is one of the largest retailers to join the line for refunds, along with more than a dozen other companies. A case challenging Trump’s tariffs under the 1977 International Emergency Economic Powers Act remains pending before the Supreme Court, which is expected to rule before June.
Costco said it was holding its place in line for refunds in case the Supreme Court overturns the tariffs, noting a separate lawsuit was needed because importers “are not guaranteed a refund for those unlawfully collected tariffs in the absence of their own judgment and judicial relief.”
The request hints at a complicated refund process for a share of the $195 billion in tariffs the federal government collected in fiscal year 2025. Supreme Court Justice Amy Coney Barrett said refunds could be a “mess” during oral arguments in the tariff challenge last month.
The company’s lawsuit, filed in the United States Court of International Trade, noted that any refunds could be void if not addressed quickly.
“This Court and the Federal Circuit have cautioned that an importer may lack the legal right to recover refunds of duties for entries that have liquidated, even where the underlying legality of a tariff is later found to be unlawful,” attorney John Brew, of Crowell & Moring LLP, wrote on behalf of Costco.
The company noted two courts, including the Court of International Trade, had already ruled that tariff authority rests with Congress, not the president.
“To the extent it is ever permissible under the United States Constitution for Congress to delegate any part of the powers vested in it by the Constitution to the President, it must do so, at a minimum, by providing an intelligible principle to direct and cabin the President’s authority,” Brew wrote in the complaint. “In IEEPA, Congress did no such thing. And there is no better evidence of Congress doing no such thing than the pell-mell manner by which these on-again/off-again IEEPA duties have been threatened, modified, suspended, and re-imposed, with the markets gyrating in response.”
A group of Democrat-led states, five small businesses and two Illinois-based toymakers challenged Trump’s authority to impose tariffs without Congressional approval under a 1977 law. That law, the International Emergency Economic Powers Act, doesn’t include the word “tariff” and has never been used to impose tariffs. They argue that only Congress has the power of the purse and that Trump can’t impose tariffs without approval from Congress.
The Trump administration says that the law constitutes a clear delegation of emergency power, granting the president broad authority to act in times of crisis.
Costco’s case could be consolidated with similar cases filed by Illuminate USA LLC, Moog Inc., Goody Foods Corp., Alcoa USA Corp. and others.
The motion to consolidate said that all the companies want the same thing.
“All plaintiffs seek identical interim relief to preserve their refund rights and the Court’s jurisdiction while the Supreme Court considers the V.O.S. Selections appeal,” the motion says. “Without such relief, entries will likely liquidate by operation of law before that decision issues.”
