U.S. importers are racing to reclaim billions in tariff payments after a long-awaited government refund portal officially went live Monday, marking a major step in unwinding disputed trade duties.

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The system, rolled out by U.S. Customs and Border Protection (CBP), is designed to process claims tied to tariffs that were struck down earlier this year. Within hours of launch, companies began flooding the platform with submissions—testing its capacity under heavy demand.

Early feedback suggests the system is holding up, though not without minor hiccups. Some users reported delays when uploading documents, with files occasionally rejected and requiring multiple attempts. Still, major outages had been feared—and so far, avoided.

Executives say preparation has been intense. Some firms assembled internal teams ahead of the launch to ensure filings could begin immediately. For companies with hundreds of invoices, the process remains time-consuming, even with batch upload options available.

The urgency stems from the sheer scale of potential refunds. U.S. authorities are preparing to return as much as $166 billion to importers following a legal ruling that invalidated the tariffs.

That ruling came from the U.S. Supreme Court earlier this year, delivering a significant blow to trade measures introduced under emergency powers. The decision triggered a scramble among affected businesses to recover funds tied to millions of shipments.

Government data shows tens of thousands of importers had already completed initial steps toward reimbursement before the portal opened, representing a substantial portion of the total refund value. However, with over 300,000 companies impacted overall, activity is expected to remain high in the coming weeks.

While it’s unclear whether early submissions will be processed faster, many firms are choosing not to take chances—opting instead to file immediately.

Industry participants say the system appears functional in its early phase, with most submissions going through successfully. However, experts caution that more complex claims—particularly those involving origin verification—could face additional scrutiny and delays.

Once claims are accepted, they are expected to move into an automated processing stage, with payments projected within two to three months. Cases flagged for inconsistencies may require manual review.

Despite the progress, some business leaders question why companies must actively apply for refunds at all, given the court’s clear ruling. Still, there is cautious optimism that the system will deliver results efficiently.

The rollout marks the latest development in a prolonged tariff dispute that has reshaped supply chains and added volatility to global trade. As companies now pivot from mitigation to recovery, attention will turn to how quickly funds are returned—and whether the system can handle the volume ahead.