Updated April 5, 2026 — Prices updated regularly from EIA data
Route • 7 states
About Interstate 94
Spanning 1,585 miles from Billings, MT to Port Huron, MI, I-94 crosses the Northern Plains and Great Lakes states. Montana's moderate prices give way to Minnesota's competitive market before rising slightly through Wisconsin and Michigan.
The average gas price along Interstate 94's route today blends prices from all the states the highway passes through. This blended average reflects both high-price and low-price state markets along the full corridor.
Interstate 94 spans 1000 miles across multiple states. For a vehicle averaging 28 MPG highway, the fuel cost varies significantly depending on which states and price zones the route covers.
Interstate 94 passes through or near major cities where competitive fuel markets and warehouse clubs offer the best prices. Look for Costco, Sam's Club, or high-volume discount stations in each major metro along your route.
A 2-mile detour to save 20 cents per gallon on a 15-gallon fill-up saves $3. With a car getting 28 MPG, the detour uses 0.14 gallons. Detours above 3-4 miles for savings under 20 cents per gallon are generally not worthwhile.
The cheapest gas along Interstate 94 is generally found in Wisconsin, where lower fuel taxes and proximity to refineries or pipelines keep prices down. Avoid fueling at highway-exit stations in Illinois, where tourist premiums push prices 15-25 cents above the best nearby rates.