Is the Costco credit card worth it? Compare incremental cash back

Hypothetical $1,000 spending comparison with a 2% benchmark

Know the current earning categories

As checked October 6, 2026, Citi’s product page lists 5% on Costco gas and 4% on other eligible gas and EV charging, sharing a combined $7,000 annual spending cap, then 1%. It lists 3% on restaurants and eligible travel, 2% on other Costco and Costco.com purchases, and 1% elsewhere. Category exclusions apply. There is no card annual fee with a paid Costco membership.

These details matter because older descriptions may show a different fuel structure. They also show why the store’s name can be misleading as a decision shortcut: the strongest percentage is not the rate on ordinary warehouse purchases. Put your spending into the actual categories rather than treating every Costco-related dollar as earning the top rate.

Separate membership value from card value

If you would keep a Costco membership regardless of the credit card, its fee is not an additional cost caused by this card choice. Evaluate the card against other cards available to you using that existing membership as the baseline.

If you would join only to obtain the card, include the membership cost in the comparison. Also consider travel time, shopping habits, and whether bulk purchases genuinely reduce spending. A high cash-back percentage does not make unnecessary purchases economical.

The membership’s own rewards, where applicable, and the credit card’s rewards are separate programs. Citi’s reward certificate FAQ distinguishes them. Keep the calculations separate and check each program’s eligible purchases and timing. Combining them casually can double-count a benefit or apply it to spending that does not qualify under one of the programs.

Compare against a straightforward alternative

Use a hypothetical no-annual-fee card returning 2% on all purchases as a benchmark. This is a comparison assumption, not a recommendation or claim that every reader qualifies for a specific offer. For each category, calculate Costco-card rewards minus the benchmark rewards on the same spending.

Consider a fictional member spending $3,000 on Costco gas, $1,000 on other eligible fuel, $4,000 on restaurants and eligible travel, $6,000 on other Costco purchases, and $5,000 elsewhere. Applying the stated rates within the fuel cap produces $150, $40, $120, $120, and $50, totaling $480. The hypothetical 2% benchmark yields $380 on $19,000, a $100 difference.

That difference is more informative than the $480 headline. It shows the benefit of choosing this card instead of the alternative, before considering redemption convenience, membership costs if incremental, and borrowing charges.

Consider a two-card approach without overcomplicating it

In the example, the $5,000 of ordinary spending earns $50 at 1% rather than $100 at the hypothetical 2% rate. Using the alternative for that spending would add $50 of rewards, assuming no other costs or constraints. A simple category rule can improve the result.

However, do not build a complicated system that creates missed payments or administrative stress for a modest gain. The value of an extra $20 or $50 annually depends on how easily you can manage another account. Clear payment reminders and a manageable number of cards matter more than maximizing every purchase to the last cent.

Review actual merchant coding after a small representative purchase. A business that sounds like a restaurant or fuel seller may not qualify as expected under issuer definitions. Use the posted rewards and current terms rather than relying only on the merchant’s name.

Account for the annual redemption process

Citi states that rewards are provided as an annual certificate after the February statement closes and can be redeemed at US Costco warehouses, including Puerto Rico. Its terms specify redemption conditions and the certificate’s deadline. Review the current Citi reward information before treating rewards as cash available whenever you want it.

This timing may be acceptable for a regular warehouse shopper, but it is a drawback for someone who prefers monthly statement credits or expects to stop shopping at Costco. Put a reminder in your calendar and verify how you receive the certificate.

Do not mentally use unredeemed rewards to fund today’s spending. They are a future benefit subject to the program rules, while the card bill is a current obligation. That distinction is especially important if a large annual reward makes a high monthly balance feel more affordable than it is.

Stress-test fuel and travel assumptions

The combined fuel cap deserves attention for households with substantial driving. Track annual eligible spending rather than multiplying all fuel purchases by the top rate without a limit. Also distinguish Costco fuel from other eligible gas and charging because their stated rates differ.

If you drive less next year, change vehicles, stop commuting, or move away from a convenient warehouse, recalculate. Travel and restaurant spending can also fluctuate. A card that fits last year’s habits may have only a small advantage under the coming year’s budget.

Use three scenarios: normal spending, reduced fuel and travel, and a major change in membership use. If the card only wins in the highest-spending case, avoid treating the optimistic outcome as a reliable annual benefit. Rewards should follow spending decisions, not create them.

Keep borrowing and account terms in view

Cash back is not a reason to carry a balance. As an illustration, a $1,500 balance at a hypothetical 24% annual interest rate represents about $30 for one month using a simple approximation. Actual interest depends on the card agreement and balances. Several months of charges can erase the incremental rewards in the worked example.

Review the actual APR, payment terms, fees, and eligibility shown by Citi for your account or application. Do not use a stale rate from another website as your borrowing assumption. If you need to finance a purchase, compare financing costs directly rather than trying to offset them with rewards.

Before changing or closing an existing account, understand outstanding balances, reward status, automatic payments, and any account-specific consequences. A negative rewards comparison does not establish the right timing for every account action.

Additional buying considerations

The card’s strongest case is an existing member who pays in full, uses the eligible bonus categories, and is comfortable with annual redemption. Evaluate those conditions before applying, and reassess them whenever shopping or commuting habits change.