The new federal regulations and legal policies that require credit card issuers to overhaul their business practices will also require them to significantly revamp their systems, executives say.

"The changes affect every part of the process, and when every part of the process involves technology, it's going to be a drastic and very burdensome thing for IT departments," said Michael Brauneis, director of regulatory risk consulting at Protiviti Inc., a subsidiary of Robert Half International Inc. of Menlo Park, Calif.

MasterCard Inc. said one banker has estimated that complying with the new requirement could absorb as much as 70% of his company's IT budget in the coming year.

For most issuers, everything from customer service to billing systems and pricing models must be rewritten or replaced.

Certain provisions require entirely new processes to be added to the customer information file. Among them is the requirement that consumers opt in to a product feature that allows them to pay a fee to exceed their credit limit.

Some banks are looking at ways to comply without losing revenue. One solution: instant opt in via a text message. "They're looking for something that could realistically be done so that it will be legal and consumers will accept the charge," said Greg Hedges, managing director at Protiviti.

For some, the rules may be too much to handle. "A lot of the smaller firms are just going to exit the business," Brauneis said. "It's already less attractive than it was a few years ago."