Delay or customers will pay — from new deposit charges to merchant fees.

That's what Wells Fargo & Co. Chairman and Chief Executive John Stumpf and Regions Financial Corp. CEO O.B. Grayson Hall said would happen unless Congress delays a cap on the fees stores pay to banks for debit card transactions.

A bill to delay the start date from July 21 to the end of 2012 or later awaits a full Senate vote.

"Hopefully, we'll all get a delay. If we can't, what do we do to offset the loss of revenue? … Unfortunately, the consumer will pay," Stumpf said at a Barclays Capital conference Monday in London, according to a Bloomberg transcript.

Wells, of San Francisco, has several options for recouping the $325 million in quarterly revenue it estimates it would lose under the Dodd-Frank Act cap, including: raising minimum account balances, introducing a debit card carrying fee and implementing surcharges on checking accounts, he said.

It also could "unbundle" the services "you provide to merchants," Stumpf said. What that means is that Wells could conceivably find ways to charge merchants for debit-processing-related services that would not fall under the cap. For example, experts say, a bank could charge stores a fee to guarantee that a transaction will clear, something they now do for free.

"You can break a debit transaction down," said Lee Manfred, a partner at First Annapolis Consulting Inc., a payment services consultant in Linthicum, Md. "It's not easy, but it's feasible."

Wells, with more than 9,000 branches around the country, is the nation's second-largest debit card issuer, Stumpf said.

Hall, meanwhile, said in a separate conference presentation that the $132 billion-asset Regions is ready to "make adjustments to our business model" to try to offset whatever revenue it loses from lower interchange fees. Depending on "how that legislation finally plays out," he said that in 2011 the Birmingham, Ala., company intends to make up for the $346 million in debit card income it collected in 2010.

The 1,700-branch lender's plan for offsetting Durbin — and other revenue-sapping regulatory changes — is twofold: go after more consumer-oriented business while figuring out how to charge for what customers had grown accustomed to getting for free, Hall said. Regions began eliminating free accounts and services a year ago.

"Now we've got to figure out a way to convince not only our customers, but also our associates who serve those customers, that banking is worth paying for," Hall said. "You'll continue to see us ramp that up."

Regions is running risky commercial real estate loans off its books. A long-term goal involves shifting its business emphasis from that market to higher-yielding credit card and auto loans. To that end, it is "evaluating" re-entering the credit cards business as a cards provider, Hall said.

"We were in that for years. We still have a credit card portfolio" that Bank of America Corp. services, he said. "We've looked at that pretty hard."

Right now so-called interchange fees are around 1% of a purchase. Under an amendment to the Dodd-Frank Act from Sen. Richard Durbin, D-Ill., the Federal Reserve has proposed capping that fee at 12 cents. Sen. Jon Tester, D-Mont., has proposed a 15-month delay.

In another presentation, TCF Financial Corp. Chairman and CEO William Cooper said he intends to carry on his court challenge to the Durbin amendment either way.

Cooper — perhaps the most vocal critic of the cap — described it as a $15 billion-a-year "raid on the banking business" that will hurt banks and the economy.

He said there's a 50% chance it will be delayed, which would buy time for the 442-branch, Wayzata, Minn., company's legal challenge.

"It's hard to believe that Congress will vote not to study something. They'll love to study it. It keeps the coffers open for political contributions," Cooper said. "I'm very optimistic on our court case. … We believe that we're right on the issue."