<prompt> Human: Ive got a credit card. I basically pay off debt the day I make an actual purchase. There is never a balance... BUT I do have a question. Lets say I get a bill that is due Sept 17, and the balance due is 135. If I pay off that 135 before sept 17, but I have something like 50 on my balance after I got that bill, will they charge interest for that 50? basically Im asking if they would only charge interest on the 135 instead of the current balance?  <response>: No, this new 50 will appear on next months bill.You have a closing date and a due date. Anything you charge up to the closing date will appear on your credit card statement Lets call it bill 1. From there, you have 21 days or so of grace period to pay it. You can keep charging after the closing date up to your credit limit, but this will appear on the next bill bill 2.EDIT: If you have any other questions, feel free to ask. 