Good credit is a powerful tool, and using your credit card responsibly is one of life's great conveniences. But for some of us, that convenience is coming at an ever-increasing price.

It's important to know that several large credit card companies have quietly jacked up late fees for customers who missed payments. Some are even taking away frequent flyer miles from late payers.

To make matters worse, many companies are cutting the number of days customers have to pay their bills, making it tougher to avoid late fees.

Your credit card company wouldn't do that to you, you say? Ho-ho, don't be too sure! The number of credit cards charging at least a $35 late fee has doubled.

Not many years ago the average card issuer gave you 31 days to make a minimum payment, but that has dropped to between 20 and 25 days, and even shorter for some cards.

So bottom line, check out the terms of your current credit cards and read the fine print before you sign up for a new one.

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