The question
On September 16, the Federal Reserve raised its benchmark interest rate a quarter of a percentage point, to a range of 3.75 to 4 percent, its first increase in three years. If you carry a balance on a credit card, here is the question worth asking: does that decision change what you pay?
The short answer
Yes, and quickly. Most credit card interest rates in the United States are variable, which means they are designed to move. When the Fed raises its benchmark, the prime rate typically follows within days, and credit card APRs, which are usually set as the prime rate plus a margin, adjust within one or two billing cycles. You do not get a vote, and you often do not even get a prominent notice. The rate just moves.
This is general information about how the system works, not financial advice about your specific situation.
How the chain actually works
Start at the top. The Federal Reserve sets a target range for the federal funds rate, the rate banks charge each other for overnight loans. That range is now 3.75 to 4 percent. Almost everything else in American borrowing costs hangs off that number.
The next link is the prime rate, the benchmark banks use for their most creditworthy customers. By long convention, the prime rate sits about three percentage points above the top of the Fed’s target range, and banks move it in lockstep when the Fed moves. When the Fed hiked on September 16, the prime rate followed, as it always does.
The final link is your card. Nearly all major credit cards issued in the U.S. carry variable APRs expressed as “prime plus a margin.” The margin is the bank’s markup, set when you opened the account based on your creditworthiness, and it typically ranges from around ten to more than twenty percentage points depending on the card and the customer. Your cardholder agreement spells out this formula, though few people ever read it.
So the arithmetic is simple: Fed raises its rate by a quarter point, prime rises by a quarter point, and your APR rises by a quarter point. The margin does not change. The benchmark underneath it does.
A concrete illustration
Imagine a household carrying a $6,000 balance on a card with a 24 percent APR. That is not an unusual situation; millions of Americans carry balances month to month. At 24 percent, the card accrues about $120 in interest per month on that balance.
Now the Fed raises rates a quarter point, and the card’s APR moves to 24.25 percent. Monthly interest rises to about $121.50. That sounds trivial, and for one quarter-point move, it is. But the Fed’s own projections suggest more increases may be coming this year, sixteen of eighteen officials expected at least one additional hike, and rate moves compound. Four quarter-point hikes take that APR to 25 percent and monthly interest to $125. Over a year, on a balance that is not shrinking, the difference between 24 and 25 percent is roughly $60 in extra interest, money that buys nothing and builds nothing.
The more important math is about time. At 24 percent APR, making only minimum payments on a $6,000 balance can keep a household in debt for well over a decade, with total interest exceeding the original balance. Every rate increase stretches that timeline a little further and raises the total cost a little higher. The rate does not have to move much to matter enormously when the balance is large and the payoff is slow.
Why cards move faster than mortgages
It helps to contrast credit cards with mortgages, because the difference explains a lot about who bears rate risk in America. A 30-year fixed mortgage locks your rate at origination; the Fed can hike ten times and your payment does not budge. Credit cards work the opposite way: the lender keeps the rate risk, and passes it straight through to you.
That pass-through is fast. Federal rules require 45 days’ notice before a card issuer raises your rate for most reasons, but there is an exception that swallows the rule here: when the rate increase comes from a change in the underlying index, like the prime rate, no advance notice is required. The new rate simply applies to new transactions immediately and to your existing balance starting with the next billing cycle in most cases. Check your statement after a Fed hike and you will usually find the new APR already there.
What you can actually do
First, know your rate. Log in to your card account or pull up your last statement and find the APR for purchases. Many people carrying balances cannot name their rate within five percentage points. You cannot manage what you have not measured.
Second, understand that in a rising-rate environment, variable-rate debt gets more expensive the longer you hold it. If you have been making minimum payments while telling yourself you will deal with the balance later, later just got pricier. Every dollar of principal you pay down now is a dollar that will not accrue interest at next month’s higher rate.
Third, look at your options with clear eyes. Balance-transfer offers with introductory zero percent periods exist, but they come with transfer fees, usually 3 to 5 percent of the amount moved, and the promotional rate expires. They can make sense as part of a disciplined payoff plan and make no sense at all if the balance just moves without the plan. Calling your issuer to ask for a lower rate costs nothing and occasionally works, especially with a record of on-time payments.
Fourth, separate new spending from old balances. The highest-return move in personal finance during a hiking cycle is almost embarrassingly simple: stop adding to a balance you are paying 24 percent to carry. Every purchase on that card is effectively financed at that rate until the balance is gone.
The bigger picture
The Fed raised rates because inflation is still running too hot, with consumer prices rising at a 3.4 percent annual rate in August, well above the 2 percent target. Higher rates are the medicine. But medicine has side effects, and for households carrying variable-rate debt, the side effect arrives fast and automatically.
Nobody at the Fed meeting on September 16 was thinking about your credit card statement. But your credit card statement is thinking about the Fed meeting. In a hiking cycle, the most powerful financial move most households can make is also the least glamorous: shrink the balances whose rates you do not control, before the next quarter point lands.
