Credit card companies are revealing some unintended consequences of the new credit reform bill that was signed into law today.

As we’ve mentioned before, some parts of the bill — like requiring larger print on credit agreements — give consumers a fair shake. But it also means banks may start charging interest on accounts that are paid on time and in full every month. That means punishment for people with sterling credit scores who have never carried a balance or paid a bill late in their lives.

From The New York Times:

Banks are expected to look at reviving annual fees, curtailing cash-back and other rewards programs and charging interest immediately on a purchase instead of allowing a grace period of weeks, according to bank officials and trade groups.

“It will be a different business,” said Edward L. Yingling, the chief executive of the American Bankers Association, which has been lobbying Congress for more lenient legislation on behalf of the nation’s biggest banks. “Those that manage their credit well will in some degree subsidize those that have credit problems.”

The Library for Economics and Liberty points out that the regulations would also tighten the credit market for high-risk borrowers.

For years, people who pay their accounts responsibly have enjoyed perks like cash back and frequent flyer miles. But with more annual fees and no grace period, it’s a fair expectation that fewer people with good credit are going to be willing to pay such a high cost for the convenience of using plastic.