Does Costco sell diesel fuel?

Yes, but not at all locations. A subset of Costco fuel stations carry diesel — typically larger warehouse locations near industrial areas, highways, or agricultural regions. The diesel pump is usually a separate island or designated lane. Check /station/costco to find Costco locations with diesel near you.

Does Sam's Club sell diesel fuel?

Yes. Sam's Club diesel availability is similar to Costco — available at select locations, not universally. Many Sam's Club fuel centers in Texas, California, and the Southeast carry diesel. Check /station/sams-club to confirm diesel availability at specific locations.

Which is cheaper for diesel — Costco or Sam's Club?

Costco diesel is typically 2–8 cents per gallon cheaper than Sam's Club diesel in markets where both are available. Both beat retail diesel stations by 10–30 cents per gallon. The exact difference depends on your region and the current wholesale diesel market.

Can semi-trucks fuel at Costco or Sam's Club diesel pumps?

Most Costco and Sam's Club fuel stations are designed for passenger vehicles and light trucks, not semi-trucks. The pump clearances and canopy heights are typically not suitable for Class 8 tractor-trailers. Owner-operators with pickup trucks or smaller diesel vehicles can use them freely.

Is a warehouse club membership worth it just for diesel savings?

For diesel pickup truck drivers, absolutely. A driver filling 30 gallons of diesel weekly and saving 20 cents per gallon saves $312 per year — well above the $65 Costco or $50 Sam's Club membership cost. For fleet operators fueling multiple vehicles, the ROI is even stronger.

Costco vs Sam's Club Diesel Prices: Which Warehouse Club Is Cheaper? | Fuel Diesel Near Me

If you drive a diesel truck, own diesel equipment, or manage a small fleet, Costco and Sam's Club are two of the most reliable sources of below-market diesel fuel in the United States. But there are important differences in availability, pricing, and who these stations actually serve well.

Here's an honest comparison for diesel buyers specifically.

Diesel Availability: Not Every Location Has It

The most important thing to know upfront: neither Costco nor Sam's Club carries diesel at every location. Both chains offer diesel at a subset of their fuel stations — typically locations near:

Major highways or interstates
Agricultural or rural areas with high diesel demand
Industrial and commercial zones

In states like Texas and California, diesel availability at warehouse clubs is more common. In densely urban areas, it's less common. Before making a dedicated trip, confirm diesel availability using /station/costco for Costco locations and /station/sams-club for Sam's Club locations.

Price Comparison: Costco vs Sam's Club Diesel

In markets where both chains carry diesel, Costco is typically 2–8 cents per gallon cheaper than Sam's Club. Both are 10–30 cents per gallon cheaper than most nearby retail diesel stations.

Here's a simplified comparison:

Costco diesel — typically 15–30 cents below local retail stations. Membership: $65/year. Payment: Visa credit cards and debit cards only.

Sam's Club diesel — typically 10–25 cents below local retail stations. Membership: $50/year. Payment: most major credit cards, Sam's Club app (Sam's Club Pay), and debit cards.

The membership cost difference ($15/year) is quickly offset by Costco's generally lower diesel price if you fill up regularly.

Who Benefits Most from Costco Diesel

Costco diesel is best for:

Diesel pickup truck owners (Ford F-250/F-350, Ram 2500/3500, Chevy Silverado 2500HD, etc.)
Farmers and ranchers fueling diesel equipment from pickup trucks
Small business owners with diesel service vehicles
Anyone who already shops at Costco and can combine the fuel stop with a shopping trip

A Ford F-350 with a 38-gallon tank saving 25 cents per gallon saves $9.50 per fill-up. Filling up weekly, that's $494 per year in diesel savings — nearly 8x the cost of the Costco membership.

Find Costco diesel locations near you at /station/costco, or browse by state at /state/tx for Texas or /state/ca for California — two states with the highest density of Costco diesel pumps.

Who Benefits Most from Sam's Club Diesel

Sam's Club diesel is best for:

Walmart/Sam's Club shoppers who already have a membership
Drivers who prefer paying with non-Visa credit cards (Sam's Club accepts more card types)
Buyers in the Southeast and Midwest where Sam's Club has stronger coverage than Costco
Anyone who wants to use the Sam's Club app for a seamless pay-at-pump experience

Sam's Club's $50/year membership is $15 cheaper than Costco's base membership. If you only fill up 10–12 gallons of diesel per week, the lower membership cost may make Sam's Club the better deal overall even if Costco's per-gallon price is slightly lower.

Find Sam's Club diesel locations at /station/sams-club, or check /state/tx and /state/ca for major diesel pump locations in high-traffic states.

Diesel Quality: Is It the Same?

Both Costco and Sam's Club sell ASTM-grade ultra-low sulfur diesel (ULSD) that meets all federal standards. Neither chain markets their diesel as a "premium" or additive-enhanced product the way some truckstop chains do with their branded additives. For standard diesel engine use, the quality is equivalent and fully compliant.

If your diesel vehicle or equipment requires a specific additive (cetane booster, anti-gel, etc.), you'd need to add that separately regardless of where you fuel.

Semi-Trucks: Warehouse Clubs Are Not the Right Option

One important limitation: Costco and Sam's Club fuel stations are not designed for semi-trucks or Class 8 vehicles. The canopy clearances are typically 13–14 feet, which is too low for a standard trailer. The pump islands are set up for passenger vehicle and light truck spacing.

If you operate semi-trucks, your best discount diesel sources are cardlock networks (CFN, Comdata, EFS), truckstop chain discount programs (Pilot Flying J, Love's, TA-Petro), and bulk fuel delivery directly to your terminal.

For diesel pickup trucks, service vans, and light commercial vehicles, however, warehouse clubs remain the single best retail source of cheap diesel in most U.S. markets.

The Bottom Line for Diesel Buyers

For diesel pickup drivers and small fleet operators with light commercial vehicles:

Costco wins on price if you're already a member or fill up frequently enough to justify the membership
Sam's Club is a strong second option, especially in the Southeast/Midwest and for non-Visa card users
Both beat every nearby retail diesel station by a wide margin, nearly every day of the year

Use our diesel fuel finder at /fuel/diesel to check current diesel prices near you, compare warehouse club options, and plan your most cost-effective fill-up.

Costco vs Sam's Club Diesel Prices: Which Warehouse Club Is Cheaper?