Costco has filed a lawsuit against the Trump administration seeking a refund of customs duties paid following the imposition of new global tariffs, introduced by the US president in 2025 through a unilateral declaration of a national emergency. The lawsuit, filed in the US Court of International Trade, seeks to prevent Customs and Border Protection (CBP) from finalizing the retailer's payments on December 15, making any potential refund more difficult.
Costco's lawsuit states that "plaintiff seeks relief from the impending liquidations to ensure its right to a full refund is not jeopardized." The company thus joins a growing group of companies—including Revlon Consumer Products and Bumble Bee Foods—challenging the legitimacy of the tariffs based on the emergency power provided by the International Emergency Economic Powers Act (IEEPA).
The matter is currently before the Supreme Court, which is examining two joint appeals: Learning Resources Inc. et al. v. Trump e VOS Selections Inc. et al. v. TrumpDuring the November 5 hearing, the justices expressed skepticism about the administration's interpretation that the IEEPA allows the President to impose unlimited tariffs after declaring a state of emergency, even though the law does not explicitly grant such authority.
The Supreme Court is expected to rule soon, but Costco had to act immediately to keep its refund options open. The lawsuit states that "even if the IEEPA duties and related executive orders are declared unlawful, importers are not guaranteed a refund absent their own legal action."
The retailer is also seeking an injunction to prevent the administration from imposing new IEEPA duties and a full refund of those already paid. Costco has announced it will also file a request for a preliminary injunction to suspend future payments.
According to analysts cited by Supply Chain Dive, Customs and Border Protection could face an unprecedented wave of refund requests if the Supreme Court were to invalidate the tariffs. A PricewaterhouseCoopers assessment estimated that total tariffs collected through the IEEPA in 2025 would reach $108 billion by October.
