Flexport founder and CEO Ryan Petersen is making a bullish case that U.S. importers will eventually recover duties paid under tariffs now ruled unconstitutional, and he’s built a free tool to help businesses find out exactly how much they may be owed.

The Flexport Tariff Refund Calculator lets importers upload their 2025 Entry Report from U.S. Customs and Border Protection, freely available online, and instantly see a breakdown of duties that may qualify for a refund by category.

One small clothing company that ran its numbers through the tool reportedly found $70 million in potential refunds.

Petersen Calls It A Slam Dunk

Petersen told CNBC on Monday he’s reasonably confident refunds will come, calling it a “slam dunk” case in favor of importers following the Supreme Court’s 6-3 February 20 ruling that IEEPA tariffs were unconstitutional.

He cautioned, though, that getting the money is a different story. There is no procedure currently in place to process refunds, making this a potentially long legal battle.

Importers who want to protect their claims need to file a protest within 480 days of each entry’s liquidation date, according to Petersen. The clock is already running on early 2025 shipments.

What Do Prediction Markets Think?

On Polymarket, the question of whether courts will force the Trump administration to actually refund tariffs by June 30, 2026 sits at just 23%.

The market likely reflects the sheer number of things that need to go right in a short window. No procedure currently exists to process those refunds, and the administration has shown little appetite for moving quickly on this.

On Kalshi, the market for refunds agrees with Polymarket that early refunds are unlikely.

Before April 1st is at just 13%, before July 54%, and before 2027 at 76%.

Current Tariff Regime A Headache For Importers

Petersen acknowledged the tariff landscape is difficult to follow right now.

The administration is not happy about the court ruling and is expected to explore other tariff procedures aggressively, meaning more complexity is likely ahead rather than less.

The ruling itself invalidates tariffs applied to Canada, Mexico, China, and the broader roster of trading partners targeted by the April 2025 Liberation Day executive orders.

Estimates put the total pool of potentially refundable IEEPA duties at up to $175 billion, and trade experts say actual payments could take 12 to 18 months or longer to materialize.

Treasury Secretary Scott Bessent has said authorities have not yet been instructed to repay funds, and the situation remains uncertain.

Image: Shutterstock