<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by ALadyNCal:
Your Citibank AA Debit Card MASTER CARD works at Costco? I have one of those and thought it didn't... Right now I use my American Express Delta @ Costco.
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It works because you can pay at Costco with your ATM card - it doesn't matter whether it is a Visa/MasterCard branded ATM card at all... you use it as an ATM card, not as a credit card.