Credit Card Rate Increase

FIA Card Services is changing the terms of my credit card agreement. Credit cards can be very costly if not used with moderation and responsibility. I use credit cards essentially for the rewards and for the convenience. They also help my credit score as long as I am not late on my payments. Not only do I pay by the due date, but I also pay the balance in full each month.

The APR increase, from 14.99% to 24.99%, is for cash advances only. It does not apply to purchases which remains at 14.99%. It goes in effect in January 2008.

I would never use a credit card for cash advance, so this rate increase does not really annoy me. But a sentence in the notice caught my eyes : "We increased your APR due to the balances and APRs on this account." What does this mean exactly? Why are they increasing my rate? Could it be because I am a credit card deadbeat?