Do you need to purchase a Costco gift card if you are a member to buy gas or can I use my debit or credit card?

You can use a debit or credit card.

Debit card should work fine

Lenora - you do need to be a Costco member to buy their gas. However, contrary to what Miguel said, they don't take cash, at least not at the Concord Costco on Monument. However, you can use a debit card, or any Visa charge card. (They switched from AmEx to Visa a year or two ago).

You just have to have a Costco membership and you can use cash or you credit card or debit card and at Costco gas station

Debit card

Any debt card that has money in the account.