The US agency says a system being worked out to mediate the disbursement of $166bn in tariff costs to more than 330,000 importers.

The United States Customs and Border Protection (CBP) agency has announced it will need an additional 45 days to set up a system to process refund requests for the tariffs recently struck down by the Supreme Court.

The announcement came on Friday as lawyers representing CBP were called to a closed-door meeting with Judge Richard Eaton from the US Court of International Trade.

Eaton had ruled on Wednesday that the US government owes refunds to importers who were charged tariffs under President Donald Trump’s use of the International Emergency Economic Powers Act (IEEPA).

The invocation of that law for Trump’s sweeping tariff campaign was deemed illegal in a February 20 Supreme Court decision.

In a court filing (PDF) on Friday, Brandon Lord, the director of CBP’s trade policies programme, indicated the agency would not be able to comply with the ruling from Eaton this week, which proposed automatic tariff refunds with interest.

He explained that CBP needed time to reprogram the record system it uses to catalogue the duties collected from importers.

“Given the volume of entries made each year, CBP is unable to affirmatively review and liquidate each entry, and the majority of entries automatically liquidate,” Lord said in the court filing.

“As of March 4, 2026, over 330,000 importers have made a total of over 53 million entries in which they have deposited or paid duties imposed pursuant to the International Emergency Economic Powers Act.”

Automating the process, Lord added, would save the CBP more than four million hours of manual labour. But setting up the new system would require at least 45 days. Lord underscored what he described as the vast nature of the task.

“CBP has never been ordered to, nor has it attempted to, process a volume of refunds anywhere near the volume of total entries and Entry Summary lines on which IEEPA duties have been deposited,” he wrote.

Lord, however, did not indicate when companies could expect to receive their tariff refunds.

The agency estimated that tariff deposits made under the IEEPA were valued at about $166bn as of March 4. The Supreme Court ruled last month that Trump overstepped his powers by using IEEPA to ratchet up tariffs on countries around the world, a central element of Trump’s political programme.

The US president has said that he will keep tariffs in place using alternative statutes.

Wednesday’s ruling from Judge Eaton came in response to a complaint filed by an importer, Atmus Filtration, but his decision opened the door to all importers subject to IEEPA tariffs to request refunds.

CBP said in the filing that companies will not have to file lawsuits to receive reimbursements under the system that will be set up in the coming months.

“This new process will require minimal submission from importers,” Lord said.

He did, however, signal that importers would have to register electronically to receive refunds. As of February 6, he said that only 21,423 importers had signed up, out of approximately 330,566 who were eligible.

“Until importers complete the process to receive refunds electronically, the refunds will be rejected,” Lord said.