<prompt> Human: Sorry if this is a Moronic Monday question, i cant find the answer to my question. Thank you in advance for your help.  <response>: Your question has already been answered, but Im going to elaborate unnecessarily:By custom, almost all credit cards have a grace period for purchases which gives you the opportunity to avoid interest by paying the statement balance before the due date. I dont know of any cards which offer a grace period for balance transfers and cash advances, so interest starts accruing right away.The CARD Act of 2009 mandates that, if a card has a grace period, it be at least 21 days long. However, card issuers do have the option of not offering a grace period at all. In response, card issues ensured that their purchase grace period was at least 21 days and continued not offering a grace period on balance transfers and cash advances. 