NEW YORK — A deadline is looming for millions of businesses who may be entitled to a payout in a $5.5 billion antitrust settlement with Visa and Mastercard.

The settlement stems from a 2005 lawsuit that alleged merchants paid excessive fees to accept Visa and Mastercard credit cards, and that Visa and Mastercard and their member banks acted in violation of antitrust laws.

Any businesses that accepted Visa and/or Mastercard credit or debit cards in the U.S. between January 1, 2004 and January 25, 2019 may be eligible to receive part of the settlement. Eligible owners whose businesses have since closed or went bankrupt can also submit a claim.

Mitch Goldstone, CEO and owner of the film scanning business Scan My Photos, and lead plaintiff in the lawsuit, said it has been difficult to get the news out to small businesses so they can file a claim in the settlement.

“Most eligible merchants still haven’t filed their claims, despite my efforts — such as helping design a user-friendly claim form with a simple QR barcode,” he wrote in an email. “It’s frustrating, considering it only takes a minute to file.”

The deadline to file a claim is May 31. Claims can be submitted on the claims portal PaymentCardSettlement.com and by mail if a company received a paper claim form.

Only businesses that submit a claim by the deadline will get money from the settlement. The amount of the payout for each business will be calculated after all claims are filed and validated.