If you’re gonna get kicked in the pants, wouldn’t you at least like to know why? Well, American Express is the least clear in how they communicate their penalty interest rate policies, a new Card Hub survey finds.

Credit card companies start charging you a penalty APR, raising your interest rate, for things like being more than 60 days late on payments, exceeding your credit limit, or for bouncing your payment checks.

Card Hub scoped out the fine print of the top 10 card issuers and rated each in four categories from poor to excellent: clarity on penalty APR trigger, clarity on portion of balance affected, clarity on how to get back to regular rate, and clarity on APR changes during the first 12 months.

Of the top issuers, American Express alone drew poor marks across the board for not explaining very well how the penalty APR works. Their policy doesn’t even mention that being more than 60 days late triggers the penalty APR to activate. But maybe they just didn’t have good role models; because the Federal Reserve doesn’t explain it either, except in a later explanation of how you can lose an introductory APR.

Penalty APR Study – June 2010 [Card Hub]

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