Updated April 5, 2026 — Prices updated regularly from EIA data
$3.18
Circle K Regular Unleaded — Est. price in Billings
About Circle K Fuel
Circle K is one of the fastest-growing convenience store and fuel station chains in North America, with thousands of locations across the United States. Circle K leverages high-volume fuel sales and purchasing scale to offer competitive prices below the local market average. The chain is particularly prevalent in the Southeast, Southwest, and Midwest markets.
Circle K Loyalty Program
Circle K Inner Circle rewards program offers new members up to 30 cents per gallon in fuel discounts during the first 30 days. Earn ongoing fuel credits and free items with every purchase through the app.
TOP TIER certification means a fuel brand's additives exceed EPA minimum detergency standards. This designation is recognized by major automakers including GM, Ford, BMW, and Toyota as beneficial for long-term engine health.
Circle K is one of the fastest-growing convenience store and fuel station chains in North America, with thousands of locations across the United States. Circle K leverages high-volume fuel sales and purchasing scale to offer competitive prices below the local market average. The chain is particularly prevalent in the Southeast, Southwest, and Midwest markets. The key differentiator for Circle K fuel is its proprietary additive package, specifically formulated to clean fuel injectors, intake valves, and combustion chambers.
Circle K typically prices above Costco's member-only rates. Costco fuel is consistently 15-25 cents below street prices from brands including Circle K. For membership holders, Costco is almost always the cheapest option.
Like most fuel brands, Circle K stations in Billings adjust prices 1-3 times per week in response to wholesale cost changes. Prices typically move together across a brand's stations in a market area.