US President Donald Trump has warned there would be a “complete mess” if the Supreme Court were to strike down his tariffs, in remarks that signalled his unease over the impending legal decision.

In comments on social media he highlighted how much was at stake in the decision, that could come as soon as Wednesday, and the challenges it would pose if businesses could claim refunds.

“It would take many years to figure out what number we are talking about and even, who, when, and where, to pay,” Trump said.

Trump has repeatedly voiced frustration over legal challenges to his tariffs, the central pillar of his administration’s trade strategy, and has urged the Supreme Court to rule in his favour.

If it does not: “WE’RE SCREWED”, the President wrote on Truth Social on Monday.

The tariffs, including sweeping levies Trump first announced last April, are being challenged by a number of small businesses and a group of US states. They contend that the president has overstepped his authority in imposing the extra taxes, which are levied on goods coming into the country.

If the Trump administration loses the argument, the government could have to refund some of the billions of dollars it has collected.

Tariffs imposed under the International Emergency Economic Powers Act (IEEPA) have brought in more than $130bn, according to the most recent data. That amounts to more than half of all tariff revenue – but a tiny fraction of the overall revenue collected by the government.

Refunds would be “almost impossible for our Country to pay”, Trump argued on Monday.

“Anybody who says that it can be quickly and easily done would be making a false, inaccurate, or totally misunderstood answer to this very large and complex question,” he added.

Before the case landed at the Supreme Court, two lower courts found that Trump did not have the authority to impose global tariffs. Businesses and investors are anxiously awaiting a decision from America’s top court – which has a 6-3 conservative majority.

At a hearing in November, the majority of the justices, including several conservatives, expressed doubts over the White House’s justification for the import duties, which the president has claimed are necessary to restore America’s manufacturing base and fix its trade imbalance.

The White House has said that officials will find alternative avenues, if the court does not rule in its favour. That could include existing legislation which allows the president to put tariffs of up to 15% in place for 150 days.

Trump has described the battle over tariffs in epic terms, warning a loss would tie his hands in trade negotiations and imperil national security. He has said that if he does not win the case, the US would be “weakened” and in a “financial mess” for many years to come.

But many businesses in the US and abroad, which have been paying the price since Trump imposed global tariffs last year, are hoping the court deems his levies illegal.

Lawyers for the challenging states and private groups say IEEPA – the 1977 law the Trump administration invoked to impose the steepest tariffs – never mentions the word “tariffs”. They contend that only Congress can establish taxes under the US Constitution.

Opponents have also challenged whether the issues cited by the White House, especially the trade deficit, represent emergencies.

At the November hearing, the justices spent relatively little time on questions about refunds. Judge Amy Coney Barrett, who was appointed to the Supreme Court by Trump, did note that any refund process could become a “complete mess” – language Trump echoed.

Some businesses have told the BBC that while they would try to recoup money if the government is forced to issue refunds, the payments would not make up for the disruption caused by the Trump administration’s trade policies.

© 2026 BBC News