This article first appeared on U.S. News and World Report Money.

Personal finance writers, whether on the internet, in magazines, in books, or elsewhere, are usually very strong advocates of investing. There’s good reason for that, of course: assuming that you’re in a financially stable position, investing in things such as the stock market or real estate is one of the best possible uses for your money.

The problem comes with that assumption of stability. The average American household carries just shy of $8,000 in credit card debt. In other words, quite a few American families are carrying enough credit card debt that their financial lives are adversely affected. At the same time, the average credit card interest rate hovers around 15% .

Taking those two numbers together, the average family is going to face more than $1,000 in pure credit card interest over the next year. That interest is money that’s simply lost.

This isn’t an unfixable problem, though. Every dollar that you pay toward your credit card debt reduces the amount of interest that you’re going to pay over the long term. In fact, the reduction is equal to the interest in that credit card.

Let’s say you pay off $1,000 on the balance of a credit card with a 15% interest rate. The result of that extra payment is that you’ll owe $150 less on your credit card bills over the coming year – and for each subsequent year.

In other words, making an early payment on your credit card debt is the same as an investment.

In fact, I’d argue that it’s an extremely good investment. Accumulating credit card debt is a huge mistake, but if you’ve already got high interest credit card debt, paying it off is likely the best investment available to you.

Here’s why.

First, the return blows away what you can expect to get in an average year from stocks or real estate. Even optimists have a hard time arguing that you’ll beat 8% on the stock market in an average year. It’s a bad idea to expect returns like that with real estate, either.

Second, the “return” you get from paying off credit cards early is tax-free. You don’t owe income taxes on the savings you get from lower credit card bills. However, if you take any capital gains on your stock or real estate investment, the IRS is going to be mighty interested in your moves.

Third, eliminating credit card debt improves your cash flow. Each month, you have a certain amount of income and a certain pile of bills to pay. Investing occurs with the money that’s left over in this picture. However, if you focus on paying off debts early, your monthly cash flow will improve as soon as those debts are eliminated. You’ll have more cash to invest and more life flexibility, too.

Given these factors, my advice is simple: if you have high interest credit card debt, your financial focus should be on eliminating that debt before investing.

There is one exception to this rule: you should take advantage of any matching funds you get for investing. For example, if your employer offers matching funds in your 401(k), you should invest whatever is needed to get every drop of matching funds. Why? Matching funds are essentially an immediate 50% or 100% return on your investment. That’s something well worth taking advantage of.

Without such offers on your plate, however, your focus should be on eliminating your high interest debts above all else without incurring more debt. Doing so will provide the best return you can get for your money.