Why Don't I Get 4% Cash Back at All Gas Stations with My Costco Visa?

Accurate as of: March 14, 2026

The Costco Anywhere Visa^® Card by Citi advertises an attractive 4% cash back rate on "other eligible gas and EV charging purchases worldwide" (on the first $7,000 combined annual spend). However, many cardholders are frustrated to find they only earn the base 1% back at common locations like Circle K, Walmart, or supermarket gas stations.

The reason for this discrepancy comes down to something called the Merchant Category Code (MCC), which is crucial to understanding where you can truly earn that 4% bonus.

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The Problem with "Convenience Store" Codes

Credit card networks (Visa, Mastercard, Amex) assign a 4-digit Merchant Category Code (MCC) to every business to classify what type of goods or services they primarily sell.

• The 4% cash back rate is intended for businesses coded as a "Service Station" (MCC 5541) or "Automated Fuel Dispenser" (MCC 5542).
• Locations like Circle K or gas stations attached to supermarkets and superstores are often coded as a "Convenience Store" (MCC 5499) or "Miscellaneous Food Store."

Citi's terms and conditions explicitly exclude gas purchased at "superstores, supermarkets and warehouse clubs other than Costco or for fuel used for non-automobile purposes" from the 4% bonus category.

Pro Tip: Some user reports suggest you may be able to earn the 4% cash back if you pay at the pump rather than going inside the convenience store. Paying at the pump often forces the transaction to use the "Automated Fuel Dispenser" code (MCC 5542), which is generally eligible for the higher rate.

The Reality of the 4% Category

Today, roughly 80% of all gas stations in the U.S. have a convenience store on-site. This means the "eligible" 4% category is much narrower than it sounds. User experiences confirm this frustration, with purchases at convenience stores like Circle K coding as car washes or other categories, resulting in only 1% back.

Summary: Where to Earn Max Rewards

To ensure you get the maximum cash back with your Costco Anywhere Visa^® Card by Citi:

• 5% Cash Back: Exclusively at Costco's own gas pumps. This is a reliable 5% every time.
• 4% Cash Back: At standalone, traditional gas stations that don't primarily identify as convenience stores (or by paying at the pump as a workaround).
• 1% Cash Back: At convenience stores, superstores, and supermarkets with gas pumps (especially if you pay inside).

Understanding the complex world of merchant codes helps cardholders navigate these exclusions and manage expectations for their rewards.

For a comprehensive review of all the card's features, benefits, and drawbacks, read our main guide: Costco Anywhere Visa^® Card by Citi benefits and features.