Every financial adviser has their preferred method for paying down credit card debt. Some say start with the card with the highest balance. Some recommend starting with the lowest balance so you can earn a quick 'win' once you pay it off. And others prefer what I discovered was the smartest method. Start with paying down the card with the highest interest rate first.
Now, I know what you are saying...'why should I believe this guy who isn't a finance guru?' I'll tell you why. Because I have had debt...lots of it and I spent years experimenting with different methods. I want to save you the trouble and all the years of failed efforts that I experienced.
Starting with your highest interest rate card is one of the most important lessons you will learn. It may have a high balance and it may take you a while to earn a win, but once it's paid off, you will find it much easier to pay off the rest of your debt.
Each month, try to make a double payment to the card with the highest interest rate while continuing to pay the minimum on the other cards. With many cards charging double-figure interest rates, it will take you years, if not decades to pay off the balance should you just pay the minimum each time. If you pay the minimum on these high rate cards, you will never feel as if you are making a dent in your debt and you will begin to feel frustrated. How many times have you said to yourself, "I feel like this was the same amount as last month!" In most cases, it is the same amount as last month - or close to it - because of the high interest rate.
Once you pay off the card with the highest interest rate, go to the card with the next highest rate and so on and so forth.
There are very few investment vehicles that will earn 15% or more - guaranteed. However, your credit card company is guaranteed to charge you 15% each billing cycle, so paying off those high rate cards if almost the equivalent of earning 15% on your money. If you think of it in those terms you will surely realize that starting with the highest rate and working your way down makes the most sense.