With Citi Costco card, which gas stations earn 4% cash back?

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The Costco Anywhere Visa® Card by Citi is one of the best gas credit cards out there. However, some people have asked why they don’t receive 4% cash back at every gas station instead of just at a Costco station. Which gas station gives the 4% cash back then?

As Costco’s website describes it, the card earns “4% cash back on eligible gas worldwide, including gas at Costco, for the first $7,000 per year in gas purchases and then 1% thereafter.” The website goes on to note that you do not receive the 4% on “gas purchased at superstores, supermarkets, convenience stores and warehouse clubs other than Costco or for fuel used for non-automotive purposes.”

It’s a no brainer – if you’re a Costco member the Costco Visa can be a good deal. There’s no annual fee, aside from the Costco membership fee you already pay, and using the card at Costco and elsewhere can deliver significant rewards.

Other than on eligible gas purchases, the Costco Visa also earns 4% on EV charging purchases, earns 3% on restaurants and eligible travel, 2% back on Costco purchases and 1% on everything else. However, one of the biggest draws, as mentioned, is the 4% bonus on gas.

Which gas stations will earn you 4%?

When Costco and Citi first rolled out the card in 2016, there was some confusion about where the 4% back on gas would be earned. You definitely earn it when you fuel up at Costco – which tends to sell cheaper gas than a typical gas station. But company representatives said you also receive it at other gas stations, too.

As with other category bonuses, whether or not you receive the bonus for a particular type of purchase depends on how a merchant is coded by payment networks using what is known as the merchant category code (MCC).

Card companies know what type of merchant you are charging at only via the merchant category code (MCC) that the card networks assign to individual businesses. Visa has separate codes for miscellaneous food and convenience stores (5499), service stations (5541) and automated fuel dispensers (5542). Supermarkets and warehouse clubs also have separate codes. Citi does not control how merchants are coded.

Citi confirmed that the Costco Visa will give 4% at merchants’ classified as gas stations. In practice, most places where you pump gas are coded as gas stations, not as convenience stores – even if they are affiliated with a convenience store that offers the usual array of gum, lottery tickets, old-looking hot dogs and cold beer.

Paying at pump or in store may affect earnings

Some card users have reported on various websites that they’ve used the Citi Costco cards at QuikTrip and Circle K and received the full 4%. Sometimes, there is a different MCC for paying with a card at the gas pump as opposed to walking inside and paying, so if you go in to pay, that might explain why you are not receiving the 4% cash back at certain gas stations. Although, in some cases you can receive the 4% when you pay at the pump and inside the store.

It would be nice to think that there is nationwide consistency in how these rules are applied, but that’s just not the way category bonuses work. Unfortunately, sometimes it’s just a matter of trial and error.

Bottom line

The next time you wonder if a particular purchase is earning rewards, remember you’re not the only one. If you’re really trying to maximize your spending, you can try to find out its MCC and see if your card earns rewards in that specific category.

If not, we suggest you avoid try a different merchant. And remember, unlike other major rewards programs, Costco rewards are paid annually, after your February billing cycle ends, in the form of a coupon that can be redeemed at Costco stores and online.