If you are a Costco customer, I have some great news for you! Costco is ending their relationship with American Express and you will now be able to use your Visa card at Costco! That also means that you won’t be able to use your AMEX (sorry guys!), but since the vast majority of shoppers have a debit or Visa card, this should open up payment options to more people. This also includes the Costco credit card which will be transitioning from AMEX to Visa. All of this goes into effect 6/20/16.