Card Agreement Terms, definition of "Grace Period"
We accrue periodic finance charges on a transaction, fee or finance charge from the date it is added to your daily balance until payment in full is received on your account. However, we do not charge periodic finance charges on your new purchases billed during a billing cycle if we receive both payment of your New Balance on your current statement by the date and time your payment is due and also payment of your New Balance on your previous statement by the date and time your payment was due.
Well, we recently requested a due date change from the 21st to the 8th - I didn't like having both of our major credit cards due at the same time of the month. We had received a statement in the mail for April 2-May 1, due on the 21st. I just paid that balance in full. While I was on the site, I happened to notice that there was another pdf statement for a billing cycle from May 2-May 19, which will be due on the new due date of June 8th. It had a finance charge on it!!
So even though we've paid every bill in full since we got the card, they tried to sneak in a finance charge in direct violation of their definition of grace period above! I e-mailed customer service right away and told them that the charge needed to be reversed pronto. I'll update once I hear back from them.
UPDATE: Charge was reversed. And as the PF blogs are so fond of doing, I "made" $90/hour in doing so (because it took me less than 5 minutes to look at the statement, confirm the term in our card agreement, and compose the e-mail to customer service). Woot!