Steptoe is a small unincorporated rural town in Whitman County, Washington, United States. Steptoe is 11 miles north of the county seat, Colfax and is 43 miles south of Spokane. A post office called Steptoe was established in 1875. The community is named after Colonel Edward Steptoe for a battle located north of Steptoe near Rosalia, Washington. References Unincorporated communities in Whitman County, Washington Unincorporated communities in Washington (state)