Costco Gas Stations Hit All-Time Volume Records Amid Fuel Price Surge

What happened

During its fiscal Q3 2026 earnings call, Costco disclosed that its gas stations experienced unprecedented demand, setting all-time volume records in the company's 50-year history. Many stations required multiple tanker truck deliveries per day to avoid running dry. The surge was driven by fuel prices climbing above $4 per gallon nationally and above $6 along the West Coast amid the ongoing war in Iran. A significant number of Costco members purchased gas at the warehouse club for the first time during the quarter. The company operates 747 gas stations, which generated 10% of overall sales last year. Costco routinely prices its fuel around 30 cents per gallon below local competitors, earning only a few cents profit per gallon compared to the typical 25- to 35-cent markup at independent stations. The company also opened a new gas station in East Hanover, New Jersey, featuring capacity for 32 vehicles simultaneously and offering Kirkland Signature gasoline with five times the EPA detergent requirement.

Why it matters

The gas volume surge directly boosted warehouse traffic and same-store sales, which rose 9.8% year-over-year, the highest increase in over two years. About half of gas customers entered the warehouse after filling up, driving a 5% increase in foot traffic. However, because gasoline is among Costco's lowest-margin products, the sales mix shift reduced the company's overall gross profit margin by two-tenths of a percentage point last quarter. Total revenue reached a record $70.53 billion including membership fees, beating the $69.68 billion consensus, though earnings per share of $4.93 fell slightly short of the expected $4.98. Membership growth of 4.1% and the executive tier reaching 41.2 million members are critical, as membership fees account for roughly two-thirds of Costco's profit and help offset merchandise and fuel costs. The company extended discounts on meat and eggs to capitalize on increased warehouse visits, recognizing that members were allocating a higher percentage of paychecks to fuel.

Bigger picture

Wholesale club retailers like Costco and BJ's Wholesale Club typically benefit when gas prices spike, as consumers are drawn to their discounted fuel offerings and often convert to memberships during these periods. Unlike independent gas stations that struggle with profitability when prices rise-since customers buy less volume and overhead costs remain fixed-Costco's membership-based model and massive scale allow it to absorb thinner fuel margins while driving warehouse sales. However, the favorable dynamics reverse when prices fall: lower gas prices historically reduce both fuel sales volume and warehouse foot traffic at Costco. Analysts expressed skepticism about whether the company can retain the momentum built during the recent price surge once fuel costs normalize. The stock fell nearly 4% the day following the earnings report, suggesting investor concern that paying 50x earnings is difficult to justify if growth tailwinds from elevated gas prices prove temporary.

What to watch

Key metrics to monitor include whether warehouse foot traffic and same-store sales remain elevated if fuel prices decline, signaling that Costco successfully converted first-time gas customers into loyal warehouse shoppers. Membership renewal rates and executive tier growth will indicate if the recent surge translates into long-term loyalty. Additionally, watch for any pricing strategy adjustments on high-traffic items like rotisserie chickens and meat, which are positioned at the back of warehouses to drive basket size. Future earnings calls will reveal whether the company's gross margin recovers as the fuel sales mix normalizes and how management balances low-margin fuel sales with overall profitability targets.