Starting Thursday, consumers will get more time to agonize over their credit card bills.

That's when two major provisions of the federal credit card act of 2009 kick in, ahead of most measures in the reform measure that don't take effect until February. Both of the new consumer-friendly provisions involve notification rules.

First, card issuers will be required to mail or deliver credit card bills at least 21 days before the due date. Currently, card companies' practices vary but most allow about 14 days from the mailing date to pay, said Adam Levin, co-founder of Credit.com.

Under the new rules, payments received by 5 p.m. on the due date must be credited the same day. Some card issuers have used morning or afternoon cutoff times to levy late fees.

The second measure will force card issuers to give customers at least 45 days notice before changing their interest rate or making other significant changes to their credit card agreement. Previously, credit card companies could raise rates and other terms with as little as 15 days' notice.

The Federal Reserve has not yet developed rules for what will be considered a "significant" change. But Mr. Levin thinks cardholders will take a broad view of the new regulations. "They may overdisclose in an effort not to run into trouble," he said.

In the past, consumers have complained about not getting enough time to act before new rates or terms kicked in. The new regulations "give people time to seriously think about what they want to do," Mr. Levin said.

One option is to "opt out" of the higher rate or other change in terms by closing the account and paying off the balance under the old terms.

Issuers won't be allowed to charge a penalty for closing the account or require that the balance be paid in full immediately. Card companies could, however, limit the payback period to five years and double the required minimum monthly payment.

Another option would be to transfer the balance to a lower rate card. The downside is the new card issuer likely will charge a balance transfer fee of 3 percent to 4 percent of the balance.

Cardholders also could choose to pay off the balance under the new higher-rate terms but use another card with a lower rate for future purchases. That strategy would avoid the negative impact that closing an account potentially could have on a cardholder's credit rating, Mr. Levin said.

Many cardholders have been facing big rate increases, higher fees and dwindling rewards in recent months as card companies scramble ahead of stricter reforms set for next year intended to ban abusive card practices and enhance disclosures.

Some of the provisions on tap for February will be:

• Prohibit card issuers from raising interest rates during the first year after a credit card is opened or from boosting rates on existing balances except in limited cases, such as when a customer falls 60 days or more behind in payments.

• Ban a practice known as double-cycle billing, in which the card issuer charges interest on paid-off balances from the previous billing cycle.

• Require issuers to disclose the period of time and total interest it will take to pay off the card balance if only the minimum monthly payments are made.

• Impose strict rules for issuing cards to people under 21, such as requiring proof that the cardholder has the ability to repay the credit or requiring a parent or guardian to co-sign for the card. In the case of a co-signer, the card issuer cannot raise the credit limit without the co-signer's written permission. The act also will prohibit unsolicited card offers to anyone under 21.

• Ban so-called universal default, when a lender raises a cardholder's interest rate because the customer is late paying unrelated bills.

• Require promotional rates to last at least six months.

• Prohibit fees when cardholders exceed their credit limit unless cardholders give issuers permission to authorize purchases that put them over the limit. In addition, issuers can't charge over-the-limit fees if cardholders exceed the limit solely due to interest charges or fees.

• Require that payments in excess of the minimum payment be credited first to any balances with a higher interest rate. "Under the old games, every payment was allocated totally to paying off the lowest interest portion of your bill," Mr. Levin said.

A year from now, another provision will take effect requiring that late payment fees, over-the-limit fees or any other fee or penalty be reasonable and proportional to the violation. Guidelines for what is reasonable will be set by the Federal Reserve and bank regulators.

For more information about the Credit Card Accountability Responsibility and Disclosures Act of 2009, visit www.creditreform.org or try the "Credit Law" section of the "Learning Center" at www.credit.com.

Those who suspect a credit card issuer has violated the new rules may file a complaint with the Federal Reserve at www.federalreserve.gov. For questions, call the Federal Reserve's help center at 1-888-851-1920.