The nation's credit card tab has reached $944 billion, according to NerdWallet. The average interest rate is about 17.7%, separate data from CreditCards.com shows. That compares to about 15.2% three years ago.
Since 2016, the Federal Reserve has made eight increases to a key interest rate that affects consumer debt. It recently indicated that rates won't move higher this year unless economic conditions change.
Nevertheless, getting your interest rate down is a key way to reduce the cost of carrying a balance month to month.
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In the CompareCards study, the average rate reduction that survey participants had been able to get was 6 percentage points. The median — half fell above, half below — was about 5 percentage points.
Say you have a balance of $5,000 on a card that charges you 24% in interest and you pay $250 a month. It would take 26 months to pay off and you'd pay about $1,450 in interest. If you could get that rate to 18%, you'd save more than $450 in interest and pay it off two months earlier, the study shows.
Schulz pointed out that if you already are paying a lower-than-average interest rate, it's less likely you'll get a huge reduction. You can also explore 0% deals, which typically charge you an upfront fee but no interest for a certain amount of time.
And, because the poll was random, Schulz said the success rate is likely not limited to consumers with high credit scores.
"That's a really positive sign and a good indicator that even folks with not-perfect credit should take time to ask," he said. "Otherwise you could end up paying more to your credit card company than you probably need to."