President Obama signs the Credit Card Accountability, Responsibility, and Disclosure (CARD) Act on Friday.

MCT / Olivier Douliery

At first glance, the sweeping credit-card legislation that President Obama signed into law Friday looks like a huge victory for consumers. The law contains relief from penalty fees and instant interest-rate spikes.

But for people who pay off their bills each month, and milk the card rewards programs for everything they’re worth, there is some cause for concern.

For months now, the card companies have been threatening to cut rewards programs sharply to make up for revenue lost because of the new restrictions.

However, this talk may be just so much saber-rattling. Card companies want to make money, and big-spending customers help them do it, even if they do not go into debt.

First, let’s lay out the things we know will change because of the new legislation.

•Card issuers will no longer be able to raise interest rates on existing balances. The exception is if a payment is 60 days late; at that point, there’s no cap on how much they can hike rates. If the cardholder pays the minimum balance on time, though, the lender would be required to restore the lower rate after six months.

•Banks must send out your bill no later than 21 days before the due date. They cannot send it with, say, 14 days to go, hoping that you won’t get a check back in time to avoid a late fee.

•If the card company gets your payment by 5 p.m. on the due date, it’s on time, according to the new rules. No more of this early morning deadline nonsense, which led to late fees for payments that arrived with the afternoon mail. Also, no more late fees if the due date is a Sunday or holiday and your payment doesn’t arrive until a day later.

•If you’re paying different interest rates on the debt on a single card — one for a cash advance, another for a balance transfer and a third for a new purchase — when you make a payment over the minimum balance, banks will have to apply it to the highest-interest debt first.

•Banks must now ask you to opt in before granting you the “privilege” of spending more than your credit limit and paying a fat $39 fee for that privilege.

•Those 21 and under will need to show they have an independent source of income to get a credit card. Otherwise, they will need a co-signer.

•Consumers will have to get 45 days’ notice and an explanation before their interest rate could be increased.

•If a company uses “risk-based pricing” to raise rates on riskier borrowers, they have to use that same methodology to lower rates when appropriate.

•The Federal Reserve in coming months will determine what constitutes “reasonable and proportional” penalty fees. This might include a cap on the dollar amount card issuers could charge for penalties such as late fees.

•Card issuers can charge a fee for over-the-phone payments only if you speak with a live operator. Charges will no longer be allowed for automated phone or online payments.

•Card holders will be able to clearly see how much it’s costing them to borrow. For instance, monthly bills will come with little boxes stating how much they’ve paid in interest and in fees year-to-date. Statements will also spell out how long it will take to pay off a balance if only a minimum payment is made. And companies will need to include a toll-free number where the cardholder can get information about credit counseling.

So will credit card companies kill reward programs altogether, or scale them back drastically? Of course not.

“If you strip away the reward component of a credit card, it’s essentially a commodity,” said Rick Ferguson, editorial director at the loyalty marketing company LoyaltyOne. “The reward is what gives it its personality. It works from a branding perspective as well as a mechanism to influence customer behavior and consolidate spending on a particular card.”

That last part is crucial. People who spend a ton generate fees galore from merchants that go to the card company. So you may soon see card companies giving more goodies or lowering annual fees for people who hit certain spending thresholds each year. American Express already does this on a number of cards.

Unfortunately, the law also doesn’t cap interest rates. While lenders generally can no longer raise rates on existing balances — at least until the cardholder is very late with payments — they can still raise them going forward.

That’s true even for people who already saw their rates climb in recent months. The bill doesn’t shield from further hikes in coming months — or ever.

“With all these limitations, [card issuers] still have a lot of freedom to charge what they want,” said Ruth Susswein, a spokeswoman for Consumer Action, an advocacy group in Washington, D.C.

But keep in mind that you may have more control over what the card companies do to you than you may think.

If you don’t like the new fees and other things that banks will be testing in the coming months, make some noise. Complaints to the higher-ups at the banks may help persuade them to head in another direction.

“Work your way up the chain,” said Dennis C. Moroney, research director for bank cards at TowerGroup, a MasterCard-owned financial services consultant. After all, it may cost less to appease you than it would to replace you.

With Associated Press reports