Rotating reward categories promise bonus earnings on spending that shifts through the year. That pitch can crowd out a plainer question: what does it cost to borrow on this card? For anyone who carries a balance, even some months, the interest rate deserves a look before the rewards do.

Close-up of a folded credit card disclosure booklet on a kitchen table in soft daylight, with its rate tables blurred beside a mug.
Standard credit card disclosure tables outlining purchase interest rates, promotional periods, and variable APR index terms.

This guide sticks to what federal sources say about card pricing. Those sources do not explain how rotating categories, quarterly caps or activation rules work, so check those details in each issuer's own terms. They also do not say how to value rewards against interest. You will have to run that math yourself.

Start with the full APR section

According to the CFPB's Know Before You Owe materials, most cards carry more than one APR. Different rates apply to different transaction types and time periods. Purchases, balance transfers and cash advances can each have their own rate.

The same guidance says to compare the whole APR section, including fees, and not only the headline rate. It also says that if you carry a balance even some of the time, a lower APR costs less. That is the core test for a rotating-rewards card. A bonus category only helps if the interest on a carried balance does not swallow it.

The gap between issuers can be large. In a February 2024 survey, the CFPB reported that the 25 largest issuers charged interest rates 8 to 10 points higher than small and medium-sized banks and credit unions. The agency estimated that gap can mean $400 to $500 in extra annual interest for the average cardholder. Whether a given card's rewards outrun a difference like that depends on how much you spend and how much you carry.

Check whether the rate is fixed or variable

Card APRs are either fixed or adjustable based on an interest rate index, as the CFPB credit card consumer portal explains. A variable rate can move with its index. The number on your opening disclosure may not be the number you pay a year later.

Federal guidance also sets some limits. A card's interest rate on existing balances generally cannot go up unless the cardholder is late on payments. For future purchases, a company can typically change terms, but it must generally give 45 days' notice of significant changes.

That notice window is short. If you picked a card for a seasonal bonus, read any mailed or emailed change notice when it arrives. A higher purchase rate on new spending can arrive with only that much warning.

Treat promotional rates as temporary

Some cards offer an initial or promotional APR for a limited time, followed by higher long-term APRs. The CFPB flags the risk plainly. A low rate that ends and steps up can raise interest costs if a balance remains. Find the exact end date in the agreement and the rate that replaces it.

Timing matters too. The CFPB says most issuers calculate interest daily, so paying all or part of a balance sooner means less interest. That is a reason to pay what you can as soon as you can, not a reason to carry a balance for rewards.

Deferred interest is a separate topic. The CFPB names it as an area of its card market review, but the sources used here do not explain how it works. Do not assume it behaves like a standard zero percent offer. Ask the issuer, and get the answer in writing, before you rely on any financing plan.

Use public CFPB data to compare cards

You do not have to rely on advertising summaries. Every six months the bureau publishes its Terms of Credit Card Plans survey, with data from more than 150 issuers. The CFPB has retired its interactive comparison tool. It says the data and the tool's code remain public for independent use.

The bureau also reviews the card market every two years under the CARD Act of 2009. Its 2025 report covers promotional interest rates, deferred interest and spending by merchant category. It is a useful check on what issuers say in their marketing.

Fee limits shift as well. The CFPB adjusts Regulation Z dollar amounts for inflation each year, including safe harbor limits on issuer fees, per its consumer cards resources. Use current written disclosures, not old summaries.

Questions to ask before you apply

Build a side-by-side comparison around the terms that set your borrowing cost. Start with these questions from the CFPB's guidance:

  • When does any promotional APR end, and what rate applies after that date?
  • Is the APR fixed or variable?
  • What rate applies to new purchases, balance transfers and cash advances?
  • What fees appear in the full APR section, not only the headline rate?

Then add the questions the federal sources leave open. How do the rotating categories work, and is there a spending cap on bonus earnings? Does the card require you to sign up for each period? Those answers live in the issuer's terms, not in the sources here.

If you expect to carry a balance, put a number on it. Estimate a year of interest at the card's purchase APR. Estimate the rewards you would realistically earn. If the first figure is close to or above the second, the lower-rate card is the safer pick.

Please seek a professional. This article is general information, not financial, tax or insurance advice. Please seek a licensed financial, tax or insurance professional about your own situation.