Costco gasoline is not a rebranded Shell product. Both companies sell fuel that must meet the same U.S. EPA gasoline standards, but they buy from regional terminals, blend their own detergent packages, and price the fuel differently.
In the United States, Costco’s Kirkland Signature gasoline is a licensed TOP TIER™ fuel. Many Shell stations also sell TOP TIER gasoline, including Shell’s premium V-Power grades. That means both brands can meet the same detergent minimums automakers asked retailers to exceed — it does not mean the gallons are chemically identical.
What is actually the same
A gallon of regular unleaded at either brand is still gasoline with a posted octane rating (usually 87 AKI in most of the U.S.). Retailers pull base fuel from the same kinds of pipelines and terminals. Federal rules cap sulfur, set vapor-pressure limits by season, and require a minimum additive treat rate. If your owner’s manual asks for 87 octane regular, either brand can meet that octane number.
What is different
- Detergent package. Shell markets proprietary additives in V-Power. Costco does not sell Techron or V-Power; it uses a TOP TIER detergent treat that meets the program’s deposit tests. See whether Costco gas has additives and whether it contains Techron.
- Price and access. Costco pumps are members-only and are usually cheaper than nearby branded stations. Shell is open to the public and often runs a rewards program instead of a membership gate.
- Network. Shell has far more locations. Costco fuel is only at warehouses that have a gas station — browse U.S. Costco gas prices, Canada, or the United Kingdom.
Which should you buy?
If your car calls for regular 87, Costco’s TOP TIER regular is a solid member choice and is typically the better price. If you want Shell’s branded premium package, or you are not a member, Shell is the more convenient network. For a side-by-side, read Costco vs Shell gas. Estimate trip cost with the fuel cost calculator.