Mr. Fox, The IRS regards credit card charges (payments made by Visa, MC, AMEX, etc. to be the same as cash payments. In effect, you are taking out a loan and paying a bill. As a side note, this is also a valid way of making charitable contributions. Maybe the difference between a charge card and open accounts payable (such as an open account at your supplier) is the fact that a third party is involved. I do know that it is a valid "cash" payment for tax purposes.