<prompt> Human: This might not be the best place to ask, but this is irritating to me. Is there any good reason? I know they are not gaining any interest on it, so is there some technical reason?  <response>: Youre correct, the system is set up to instantly authorize sales, not so for credits. Even though sales dont actually settle and deposit until later, the sale amount appears on the customers card almost instantaneously. This helps ensure that the funds will be available so that merchants may process the sale. Refunds are processed like settled transactions and usually take a couple of days to fully post on the customers account. Its a practical consideration since its usually important for a merchant to know instantly whether the customer can cover the sale amount. Refunds do occur much less frequently, and the issuing bankcard company more or less determine when refunds post to customer accounts. Source: I work in the processing industry. Long time lurker here in PF, thought this would be an appropriate time to introduce myself! 