There’s good reason why banks are pushing the latest flashy credit card.

For the first time ever, credit-card interchange fees, the amount a merchant pays card networks every time a customer uses a credit card to make a purchase, have exceeded the amount customers pay in overdraft fees. Total overdraft fees totaled $33.3 billion in 2016, just shy of the $33.8 billion financial institutions collected in credit-card interchange fees, according to a new analysis of service fees from Moebs Services, a Lake Forest, Ill.-based firm that researches financial institutions.

Overdraft revenue is up only slightly, but still down from its peak of $37.1 billion in 2009 as banks have been required to get customer consent to opt into overdraft facilities since 2010 and customers shy away from higher overdraft charges. In sharp contrast, interchange fees have more than doubled from $18.5 billion eight years ago. The increase in these fees, particularly those shouldered by merchants, represents a “major shift” in how banks, credit unions and other financial institutions have collected fees in the last several decades, said Michael Moebs, an economist and chief executive of Moebs Services.

Moebs used data from the Federal Reserve’s Payments Study, which has tracked the amount consumers spend on forms of payment including cash, debit and credit cards every three years since 2001. The firm also estimated the average amounts financial institutions make from those transactions, while considering the amounts the merchants make. The average credit-card interchange fee is a few cents shy of a dollar, while debit-card swipe fees average 30 cents per transaction.

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The shift toward more credit-card revenue has happened as banks have boosted reward programs to give customers more incentive to use their credit cards, Moebs found. Credit-card interchange fees are typically much higher than those of debit cards, so attractive award programs help the banks push customers toward credit cards instead of debit, which often do not come with any rewards.

The drop in overdraft fees and the rise in credit-card revenue both indicate consumers are doing better financially, said Jeff Sigmund, the senior vice president of public relations at the American Bankers Association, a trade group. “As the economy has improved, consumers are spending more,” he wrote in an email. “Merchants who rely on this increased purchase volume to grow and hire are also feeling the benefits.”

Not all merchants agree with that, however. Interchange fees, also known as “swipe fees,” are about 1% to 4% per transaction, depending on the type of card used and the deal the retailer has with card networks, said Craig Shearman, a spokesman for the National Retail Federation, a trade group that has campaigned for years to lower swipe fees shouldered by retailers. “It’s a symbolic milestone in showing just how large swipe fees are,” Shearman said.

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In recent months, more lenders have given consumers access to credit cards. More than 171 million consumers had access to credit cards backed by major banks and open network card issuers in the first quarter of 2017, the most that have had access since 2005. It’s paid off: Americans also now collectively have more than $1 trillion in outstanding revolving debt, often summarized as credit card debt, the most in U.S. history.

But those consumers who pay overdraft fees are often the ones who can least afford it. Just 8% of bank account holders pay some 75% of overdraft fees, according to the Consumer Financial Protection Bureau. They typically have lower incomes and are less experienced with their finances, the CFPB found.

What’s more, some experts argue that retailers make up for the swipe fees by quietly raising the cost of their goods. That issue is “a contentious point of debate” among the merchants, card issuers and networks, according to Kendrick Sands, a senior consumer finance analyst at Euromonitor International. Card networks recently have provided merchants with consumer-spending data that could make their businesses run more efficiently and offset the swipe fees, Sands said.