NEW YORK (AP) — On Monday, a new refund system is set to launch for businesses that paid tariffs which the U.S. Supreme Court ruled President Donald Trump enforced without constitutional authority.

Importers along with their brokers can initiate refund claims through an online portal starting at 8 a.m., as indicated by U.S. Customs and Border Protection (CBP), the agency overseeing the system.

This marks the initial step in a complex process that could eventually provide refunds to consumers who were charged for some or all of the tariffs on products imported from outside the U.S.

Companies must submit declarations detailing the goods they imported, on which they paid billions in import taxes that the court later invalidated. If CBP approves the claim, it may take between 60 to 90 days to issue a refund, according to the agency.

The refund process is expected to occur in phases, initially processing the most recent tariff payments. Technical factors and procedural issues could cause delays in applications, leading to slow reimbursement for consumers.

A ruling by the Supreme Court on Feb. 20 concluded that Trump had overstepped congressional authority when he adjusted import tax rates last April, using the nation’s trade deficit as a basis for invoking emergency powers. While the majority ruling didn't cover refunds, a judge from the U.S. Court of International Trade stated last month that affected companies were entitled to monetary compensation.

Over 330,000 importers have collectively paid roughly $166 billion across more than 53 million shipments for the tariffs, according to filings from CBP. However, not every import qualifies for immediate refunds, particularly those where tariffs were estimated but not finalized or were recorded within 80 days of final tallying.

Importers need to register for the CPB’s electronic payment system to receive refunds. As of April 14, 56,497 importers had registered and were eligible for refunds totaling $127 billion, inclusive of interest.

Meghann Supino, a lawyer, urged clients to meticulously detail document numbers in their submissions to CBP. This point was echoed by other professionals emphasizing the necessity of accuracy in an electronic system with high volumes of interest.

Small businesses, such as After Action Cigars in Minnesota, have been preparing for this refund opportunity, having experienced financial strain due to federal import taxes. Despite the potential for refunds, the actual finding and processing of claims may pose challenges amid inevitable delays.

Companies that collect tariffs might not have a legal obligation to pass refunds directly to consumers, however, class-action lawsuits are being pursued against major retailers compelling them to reimburse customers. Delivery services like FedEx and UPS are likely to issue refunds directly to consumers, having collected tariffs from them at the onset.

“Supporting our customers as they navigate regulatory changes remains our top priority,” stated FedEx, who plans to begin claiming refunds on April 20.