March 1, 2026Last updated March 2, 2026, 3:56 p.m. ET
While many drivers might believe all gas stations are identical, this is actually far from the truth.
Not all gas stations supply fuel of the same quality, and there’s a good reason for this disparity. Certain brands include detergents in their gasoline that actively clean your fuel injectors and other components within the fuel system. Identifying which brands provide the best fuel can lead to a longer-lasting vehicle and smoother operation compared to using lower-grade options. Here’s how to find the highest quality gas in your vicinity:
Understanding TOP TIER Certification
A 1997 Environmental Protection Agency (EPA) mandate requires all gasoline sold at U.S. fuel stations to contain a minimum quantity of detergent. These detergents contribute to enhanced cleaning of fuel system components, such as fuel injectors and intake valves.
Many gasoline brands have their fuel evaluated and tested by TOP TIER, an organization endorsed by AAA that assesses fuel quality for both gasoline and diesel engines. Brands that successfully adhere to TOP TIER’s criteria are designated as an approved TOP TIER gasoline brand.
Bill Studzinski, TOP TIER’s program manager, explained to the Detroit Free Press, a publication within the USA TODAY Network, how a gas station qualifies to use the trademark for offering top-quality gasoline.
“If a fuel company chooses to submit their data, conforming to our standards, and their fuel is verified to maintain engine cleanliness, they are then authorized to use the trademark globally,” Studzinski noted. He further elaborated, “TOP TIER fuel provides at least double, and frequently closer to three or four times, the amount of additive found in gasoline meeting only the federal minimum.”
Which Brands Offer TOP TIER Gasoline?
Certain brands are widely recognized for supplying TOP TIER fuel, which is rich in cleaning detergents. Prominent examples that have earned TOP TIER gasoline approval include Shell, Citgo, Costco, Mobil, Marathon, and Exxon.
Does Higher-Quality Gasoline Cost More?
Gasoline prices are shaped by a multitude of factors. While many tend to equate lower prices with poorer quality, this isn’t necessarily true for fuel. If a brand carries TOP TIER approval, the quality of all its gasoline sold across the United States will be consistent, regardless of price fluctuations.
Is Using Non‑TOP TIER Gasoline Advisable?
There’s no prohibition against fueling up at a station without TOP TIER approval, but keep in mind that such fuel contains fewer detergents and will be less effective at cleaning your fuel system. Opting for high-quality gasoline can help prevent potential engine problems that may arise from prolonged use of lower-grade fuel. Nevertheless, if a TOP TIER-approved station is inconveniently far and your fuel tank is nearly empty, it’s prudent to choose the closest option.
Keenan Thompson reports on car culture for the Detroit Free Press. You can contact Keenan at [email protected], or follow his Instagram at @keenanautos. Sign up for our automotive newsletter or become a subscriber.