If, like a lot of people, you’re slowly chiseling away at the debt on a credit card with an interest rate of 15% or more, it’s so tempting to take advantage of a competing card’s offer for promotions like 0% APR balance transfers. And while that may be the way to go, there are common mistakes people make that end up negating the benefits of transferring their credit card balance.

Over at Credit.com, writer Jason Steele has a rundown of several of these mistakes. Here are the ones we think are the most relevant:

1. Not Picking The Best Offer
Sure, it would be so easy to take advantage of that promotional offer you just received offering 0% APR for 6 months on credit card balance transfers. But six months is now the absolute minimum for such offers. If you look around and do some comparison shopping, you’ll find cards offering that 0% APR deal for 12, 15, or maybe even 18 months, giving you a longer time to pay down the debt.

Just be careful and don’t use that extended 0% APR period as an excuse to rack up more debt. That’s exactly what the card company is hoping you’ll do.

You should find out what interest this account would charge for new purchases. Some will also offer promotional APR savings on new purchases for a few months, but still be aware of the eventual interest rate as it may be so high that you don’t want to risk using that card for anything other than saving money on the balance transfer.

2. Performing a Balance Transfer When You Can Pay Off Your Debt Quickly

The idea of switching all that 15% APR debt over to 0% APR may sound like a no-brainer, but most balance transfers charge a fee of 3% of the balance being transferred. So it may actually be less expensive to pay down that debt in a few months than it would be to transfer the balance.

Say you’ve got $1,000 on a credit card with 15% APR. Assuming you don’t rack up any more debt on that card, if you pay off your balance in full after three months, you’ll have paid around $26 in interest. But if you transfer that balance, you’ll pay $30 in fees.

That fee may be worth it if you need more time to pay down that debt or attend to other bills, but if you are just trying to spread out the cost of a hefty purchase over a few months you should do the math before assuming that a balance transfer is the right way to go.

3. Not Paying Off Your Debt Before the Offer Expires

In addition to racking up new debt on your new card, the bank is really hoping that you’ll make the mistake of failing to pay off that transferred balance in time.

When you make a balance transfer, it should be with the goal of getting rid of that debt, not as a way to just defer paying it off.

We suggest that you set up regular payments to that new account in an amount that will guarantee the transferred balance is paid off at least a few months before the actual APR kicks in. That way, in case you have a month where things are tight, you have some wiggle room and won’t end up paying interest on the transferred balance.

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