Is Sam's Club Gas Top Tier? Fuel Quality, Ethanol, Octane & Where It Comes From
No, Sam's Club gas is not Top Tier. We checked the official TOP TIER licensed gasoline brand list in November 2026, and Sam's Club is not on it. Costco's Kirkland Signature gas is. Sam's Club gas still meets the EPA detergent rule and the legal fuel spec, so it is safe for your car and will not void your warranty. This guide explains what Top Tier means, how Sam's compares with Costco and the big brands, and what we see at the 532 Sam's Club fuel centers we track in 44 states.
Top Tier Licensed?
No
Checked November 2026
Meets EPA Rules?
Yes
Warranty-safe gasoline
Clubs Selling Premium
100%
532 of 532 fuel centers
Premium Over Regular
+79¢
Avg $3.466 vs $4.251
Sam's Club gas quality: the quick answers
| Question | Answer | Details |
|---|---|---|
| Is Sam's Club gas Top Tier? | No | Not on the TOP TIER licensed brand list. |
| Does it meet EPA detergent rules? | Yes | All U.S. gasoline must. |
| Is Costco gas Top Tier? | Yes | Kirkland Signature is on the list. |
| Does it have ethanol? | Yes | Normally E10 (up to 10% ethanol). |
| Ethanol-free gas at Sam's? | No | None of the clubs we track report it. |
| Safe for my car and warranty? | Yes | Use the octane your manual asks for. |
Is Sam's Club gas Top Tier? What we checked
TOP TIER keeps a public list of every gasoline brand it licenses. It is at toptiergas.com. We read the full list on November 9, 2026. Sam's Club is not on it. Neither is Walmart, Murphy USA, BJ's, 7-Eleven or Speedway.
Costco/Kirkland Signature is on the list for the USA. So are Exxon, Mobil, Shell, Chevron, Texaco, BP, Amoco, Marathon, Valero, Sunoco, Phillips 66, Conoco, 76, Sinclair, CITGO, QuikTrip, Holiday and Meijer Express, among others.
So the answer to "does Sam's Club have Top Tier gas" is the same at every club. There is no Top Tier grade at Sam's, and premium is not Top Tier either. Brands license the standard for all their grades at once. Sam's has not licensed it.
How to check any station yourself
Licensed stations usually show the TOP TIER logo on the pump. If you don't see it, look the brand up on the TOP TIER list. The list can change, so check it again if you read this much later.
What Top Tier means, and how it differs from the EPA minimum
Every gallon of gasoline sold in the U.S. must contain a detergent additive. The EPA sets the minimum dose. It is called the Lowest Additive Concentration, or LAC. That rule has applied since the mid-1990s. It is a legal floor.
TOP TIER is a voluntary standard set by automakers. They thought the EPA floor was too low for modern engines. The current sponsors are Audi, BMW, Daimler Truck, Ford, GM, Honda, International, Mercedes-Benz, Stellantis, Subaru, Toyota and Volkswagen. To use the TOP TIER name, a fuel brand must:
- Use more detergent than the EPA minimum, in every grade, at every station. Our other quality guides put it at roughly two to five times the minimum, depending on the brand.
- Pass engine tests for intake valve and fuel injector deposits.
- Hold a license and accept TOP TIER's checks.
Does the extra detergent matter? AAA tested it in 2016. After 4,000 miles of simulated driving, the non-Top Tier gasolines left about 19 times more intake valve deposits than the Top Tier ones. Deposits build up slowly. They can cost some fuel economy and smoothness over many years. They do not ruin an engine after one tank.
We explain the same standard in our guides to Walmart gas quality and whether Murphy gas is Top Tier. Walmart and Murphy USA are in the same position as Sam's Club: legal fuel at the EPA detergent level, without the Top Tier license.
Sam's Club gas vs Costco and other big brands
Here is how Sam's Club compares with the stations people most often weigh it against. Top Tier status is from the TOP TIER brand list as of November 2026.
| Station | Top Tier? | Membership to buy gas? |
|---|---|---|
| Sam's Club | No | Usually. See the membership rules. |
| Costco (Kirkland Signature) | Yes | Yes |
| BJ's Wholesale | No | Yes |
| Walmart and Murphy USA | No | No |
| 7-Eleven and Speedway | No | No |
| Exxon, Mobil, Shell, Chevron, BP | Yes | No |
| QuikTrip, Marathon, Valero | Yes | No |
Costco is the clear quality pick among warehouse clubs if Top Tier matters to you. Sam's Club competes on price instead. Our Sam's Club gas prices page shows today's price at every club we track. Sam's Club runs its own fuel centers. They are not Murphy USA stations, and they are not linked to the Good Sam RV club.
Is Sam's Club gas good?
Yes, for most cars. Sam's Club gas is ordinary, legal gasoline. It has to meet the same ASTM fuel spec and EPA rules as gas at any other station. Busy clubs also sell a lot of fuel, so it doesn't sit in the tank for long. The one real gap is the detergent level described above.
Where does Sam's Club get its gas?
Sam's Club doesn't refine oil, and it doesn't sell a major oil brand. Like other warehouse clubs, it buys unbranded fuel. That fuel comes from the same regional terminals that branded stations load from. Refineries send base gasoline through shared pipelines to those terminals.
The brand difference is added at the terminal. When a tanker truck loads, the terminal mixes in ethanol and a detergent package. A Top Tier brand gets its own additive at the higher dose. An unbranded load gets an EPA-approved detergent at a lower dose. The base gasoline is the same.
Who supplies Sam's Club gas at your club? We don't know, and we won't guess. Our data doesn't include a supplier, and Sam's Club doesn't publish one. It can differ by region and change over time.
Does Sam's Club gas have ethanol?
Yes. Sam's Club regular and premium are normally E10, which means up to 10% ethanol. That is true of most gasoline sold in the U.S. A few more points:
- Ethanol-free gas: none of the 532 Sam's fuel centers we track report an ethanol-free price. If you need E0 for a boat or small engine, look elsewhere. Some Walmart and Murphy USA pumps sell it.
- E85: none of the clubs we track report an E85 price.
- E15: we don't track it, and we could not confirm a chain-wide policy. Some clubs may sell it. E15 must carry an orange E15 label on the pump. It is approved for 2001 and newer cars, light trucks and SUVs. Don't use it in motorcycles, boats, lawn equipment or older cars.
What octane grades does Sam's Club sell?
Most Sam's Club fuel centers sell two grades of gas: regular and premium. Mid-grade is rare. Here is what the 532 clubs we track post today:
| Fuel | Clubs | Share |
|---|---|---|
| Premium | 532 | 100% |
| Mid-grade | 4 | 1% |
| Diesel | 207 | 39% |
Clubs that posted a price for each fuel in our live data as of 2026-11-12. Every club we track posts a regular price.
Regular is usually 87 octane. Premium is usually 91 or 93, depending on the region. Check the yellow octane sticker on the pump. In some high-altitude areas, regular can be 85. If your manual asks for 87, don't buy 85.
Today, Sam's Club premium averages $4.251 and regular averages $3.466. That is 79¢ a gallon more, or about $11.85 on a 15-gallon fill. Premium buys higher octane. It does not buy more detergent at Sam's. If your car doesn't need premium, regular is fine. Need diesel? See our Sam's Club diesel prices.
Cheapest Sam's Club premium right now
One club per state, ranked by today's premium price.
| # | Station | Regular | Premium |
|---|---|---|---|
| 1 | Lebanon Tn Sam's Club Lebanon, TN | $2.909 | $3.099 |
| 2 | Midwest City Sam's Club Midwest City, OK | $2.819 | $3.359 |
| 3 | Plano, Ohio Dr Sam's Club Plano, TX | $2.859 | $3.359 |
| 4 | Richmond Sam's Club Richmond, VA | $3.439 | $3.439 |
| 5 | Fayetteville Sam's Club Fayetteville, NC | $2.699 | $3.449 |
| 6 | Wichita Ne, North Rock Rd Sam's Club Wichita, KS | $2.959 | $3.549 |
| 7 | Arvada Sam's Club Arvada, CO | $2.939 | $3.559 |
| 8 | Savannah Sam's Club Savannah, GA | $2.779 | $3.629 |
| 9 | Miami Sam's Club Miami, FL | $3.199 | $3.699 |
| 10 | St. Charles Sam's Club Saint Charles, MO | $3.039 | $3.699 |
Is Sam's Club gas watered down or bad?
No. The "watered down" idea doesn't hold up. Water and gasoline don't mix. Water sinks to the bottom of the underground tank, where the pump pulls fuel from. So watered gas would stall cars, not quietly stretch the supply. Modern stations also have tank monitors that alarm when water collects.
Bad gas can still happen at any station, including a Sam's Club. The realistic causes are:
- A wrong-fuel delivery. A driver drops diesel into a gasoline tank, or the reverse. In July 2025, a third-party fuel supplier did this at the Sam's Club in St. Clairsville, Ohio. Sam's Club told affected members to contact the club to file a claim.
- Water from a leak or storm. A damaged fill cap or spill bucket can let rainwater in. This affects one site, not the chain.
- Old fuel. This is a problem at slow stations. Busy clubs sell through their tanks quickly.
What to do if you got bad gas at Sam's Club
- Stop driving. If the car sputters, stalls or won't start right after filling up, don't keep restarting it.
- Keep your receipt. Note the club, pump number, grade, date and time. The Sam's Club app also keeps a record if you paid with it.
- Tell the club right away. Speak to the fuel center or a club manager. Ask how to file a claim.
- Ask your mechanic to keep a fuel sample and to write down what they find. That helps your claim.
- Call your insurer if the claim stalls. Some policies cover fuel contamination.
Is Sam's Club gas safe for your car and warranty?
Yes. Your warranty asks for gasoline with the right octane that meets the legal fuel spec. Sam's Club gas does. Federal law (the Magnuson-Moss Warranty Act) stops an automaker from requiring a certain brand of fuel to keep your warranty.
Some owner's manuals recommend Top Tier gas. That is advice, not a warranty rule. Two things can still cause trouble: using a lower octane than the manual requires, and using E15 in a vehicle that isn't approved for it. Damage from contaminated fuel is normally a claim against the station, not a warranty repair.
If you want Top Tier benefits and Sam's Club prices
- Add a cleaner now and then. A bottle of fuel system cleaner with PEA every few thousand miles helps clear deposits.
- Mix your fill-ups. Fill at a Top Tier station some of the time, especially if your car has a direct-injection or turbo engine.
- Follow your manual. If it says premium is required, buy premium. If it says recommended, regular is usually fine.
Should you buy gas at Sam's Club?
If price matters most, yes. Sam's Club gas is fine for daily driving, and it is often cheaper than nearby branded stations. If you want Top Tier detergents on every fill and you have a Costco membership, Costco is the warehouse club that offers it.
Before you go, check Sam's Club gas station hours and whether you need a membership for Sam's Club gas. If you have Walmart+, read how Walmart Plus works at Sam's Club pumps.
Frequently asked questions
Is Sam’s Club gas Top Tier?
No. Sam’s Club is not on the official TOP TIER licensed gasoline brand list at toptiergas.com. We checked the list in November 2026. Sam’s Club gas meets the EPA detergent minimum, but it is not certified to the higher TOP TIER standard.
Is Sam’s Club gas good?
Yes, for most drivers. It is legal, on-spec gasoline from the same regional terminals other stations use, and busy clubs sell through their tanks quickly. The one real difference from TOP TIER brands is a lower detergent level, which can mean more engine deposits over many miles.
Is Costco gas Top Tier?
Yes. Costco’s Kirkland Signature gasoline is on the TOP TIER licensed brand list for the USA. Among the big warehouse clubs, Costco is the one that is Top Tier. Sam’s Club and BJ’s are not on the list.
Does Sam’s Club gas have ethanol?
Yes. Like most U.S. gasoline, Sam’s Club regular and premium are normally E10, which means up to 10% ethanol. We do not see ethanol-free gas or E85 prices at any Sam’s Club in our data. Some clubs may sell E15, which must carry an orange E15 label on the pump.
Who supplies Sam’s Club gas?
Sam’s Club does not refine fuel or sell a major oil brand. It buys unbranded gasoline and diesel from fuel terminals, the same terminals that branded stations load from. The supplier can differ by region and over time, and Sam’s Club does not publish it.
Is Sam’s Club gas watered down?
No. Water does not mix with gasoline. It sinks to the bottom of the tank, and the tank monitors at modern stations alarm when water shows up. Water or wrong-fuel problems do happen, but they come from a single bad delivery or a leak at one site, not from a chain-wide practice.
Will Sam’s Club gas void my car warranty?
No. Your warranty requires gasoline of the right octane that meets the legal fuel spec, and Sam’s Club gas does. Federal law stops automakers from requiring a specific brand of gas. Some owner’s manuals recommend TOP TIER fuel, but that is a recommendation, not a warranty condition.
Check today's Sam's Club gas prices
All 532 Sam's Club fuel centers with live regular, premium and diesel prices, plus the state list.