Ethanol-Free Gas in Watertown, SD

3 verified ethanol-free gas stations

Watertown has 3 verified ethanol-free gas stations, all Casey's locations. All 3 carry 87-octane E0. For 90-octane or higher E0, the closest option is Shirleys Gas And Grocery in Eagle Bend, Minnesota, about 133 miles away. Every listing is independently verified; the most recent check in Watertown was May 5, 2026.

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Ethanol-Free Gas in Watertown

Casey's

185 4th St Ne, Watertown, SD

6058825882

oct

Casey's

20 19th St Ne, Watertown, SD

6058860292

oct

Casey's

405 10th St Sw, Watertown, SD

6058860432

oct

All South Dakota Stations

Nearby Cities with Ethanol-Free Gas

Straight-line distance from Watertown.

Slayton, MN

3 stations · 91 mi away

Sioux Falls, SD

15 stations · 96 mi away

Hutchinson, MN

3 stations · 135 mi away

Fargo, ND

12 stations · 137 mi away

Yankton, SD

3 stations · 139 mi away

Ethanol-Free Gas in Watertown: FAQ

Is there ethanol-free gas in Watertown, SD?

Yes. Watertown has 3 gas stations verified to sell ethanol-free (E0) gasoline: Casey's (3 locations).

Does Watertown have 90-octane or higher ethanol-free gas?

Not currently. Stations in Watertown top out at 87-octane E0. The nearest station with 90-octane or higher is Shirleys Gas And Grocery in Eagle Bend, Minnesota, about 133 miles away.

Which brands sell ethanol-free gas in Watertown?

Casey's (3 locations). All locations are independently verified through chain-website confirmation or direct source data; the most recent verification in Watertown was May 5, 2026.