An effort by retailers and their allies in the Senate to mandate competition to Visa and Mastercard in credit card processing has complicated efforts to swiftly pass the stablecoin bill supported by the crypto industry and President Donald Trump.

Kansas Republican Roger Marshall has proposed the amendment, backed by Illinois Democrat Dick Durbin, who previously led a successful bipartisan effort to reduce debit card fees. The credit card competition measure had the backing of Vice President JD Vance when he was a senator as well as other populist-minded Republicans.

The proposal would require large banks to offer a choice of networks for processing credit card transactions, including one outside of Visa and Mastercard. The goal is to lower fees merchants pay for the transactions by injecting more competition.

Senator Roger Marshall

“I think this is a double win for the president,” Marshall said in an interview Tuesday, saying his amendment would reduce inflation and favor Main Street merchants over Wall Street bankers. “Capitalism without competition leads to unchecked greed, and that’s where we are right now.”

Retailers also hope the underlying stablecoin bill would give them another way to bypass credit cards and the fees they charge, which are much lower in many other countries. Card swipe fees cost US merchants more than $187 billion last year, according to the Nilson Report trade publication.

Banks, airlines and other interest groups have lobbied heavily against the credit card competition measure, which could lower their profits. They warn mandated competition and lower fees could hurt customers if credit card rewards are reduced as a result of less income from merchants.

And they have allies of their own. Republican Senator Thom Tillis of North Carolina, whose state is home to major banking operations, said he would switch from supporting the stablecoin bill to trying to defeat it if the credit card provision is attached. Republican Kevin Cramer of North Dakota said he’s sympathetic to the credit card measure but would vote against the amendment given the risk it becomes a “poison pill” and endangers the stablecoin bill.

Payment company executives have been calling senators in recent weeks trying to kill the credit card provision, people familiar with the calls told Bloomberg.

Republican Cynthia Lummis of Wyoming predicted the bill would pass next week in a Bloomberg Television interview Tuesday, but called the credit card amendment “a heavy lift, to take a bill that has been carefully negotiated and add a new subject that is controversial.”

Tennessee Senator Bill Hagerty, the lead Republican sponsor of the stablecoin bill, said he also would oppose adding the provision. “It’s not a good fit,” he said.

Even if the amendment is successful, it’s not clear it would pass the US House, given Financial Services Chair French Hill has opposed it.

Other amendments proposed so far include an effort by Senator Rand Paul to require an audit of the Federal Reserve, an amendment by Senator Josh Hawley to block large social media companies from issuing their own tokens, and Democratic amendments to block Trump from profiting off of his assorted crypto ventures while in office.

Some Democrats also want to ban Tether Holdings SA transactions from being allowed via decentralized exchanges, and to further address concerns from some bankers that stablecoins could siphon off their deposits and crimp credit.

Crypto companies like Coinbase Global Inc. have been lobbying, instead, to allow interest to be paid on stablecoin accounts, but those efforts have so far been unsuccessful in persuading lawmakers in the House or the Senate.

© 2025 Bloomberg

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