Money

This is the No. 1 reason people switch credit cards

A number of factors could motivate you to get a new credit card. Perhaps it's an attractive cash-back offer or luxury travel perk. If you're flush, it might be the promise of unlimited credit.

But none of those are the most popular reason people switch cards, according to Wallethub's 2018 Summer Credit Card Survey. Of the 540 cardholders Wallethub asked, 51 percent said they switched for a better interest rate.

The average APR among those surveyed was 19 percent, and carrying a balance with an interest rate that high can be costly. The average U.S. household with revolving credit card debt pays almost $900 in interest each year.

The APR you can get is often tied to your creditworthiness. Issuers determine that based largely on your credit score, but also your debt-to-income ratio and a few other factors. Having little debt and a large income increases your creditworthiness.

If you're shopping for a new card to get a lower interest rate, do what you can to increase your attractiveness to creditors. That might mean paying off some of your debt or elevating your credit score by making payments on time and using a smaller portion of your available credit.

With a good credit score you can qualify for a balance-transfer card, which offers zero-interest introductory periods as long as 21 months, providing you with an opportunity to pay off debt.

About a quarter of the participants in Wallethub's survey said an enticing sign-up bonus motivated them to get a new card. That makes sense, too, considering how sizable those bonuses can be.

The Chase Sapphire Reserve, for example, promises users 50,000 points when they sign-up, which is worth up to $750 when redeemed for travel. Many airline-branded cards have similar offers. But a large sign-up bonus is often accompanied by an annual fee, so the bonus shouldn't be your only consideration when deciding on a new card.

There were two other popular answers, WalletHub notes: 16 percent said they switched cards because of a pre-approved offer, and 9 percent did so at the recommendation of a family or friend.

Don't miss: The best credit cards to help you get out of debt

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