The population was 2,805 at the 2010 census. The population is estimated at 2,911 per the State of Washington Office of Financial Management in 2018 making Colfax the second largest city in Whitman County behind Pullman. It is situated amidst wheat-covered hills in a valley at the confluence of the north and south forks of the Palouse River. U.S. Route 195, which forms the town's main street, intersects with State Route 26 at the north end of town; in the past, Colfax also lay at the junction of three major railway lines. It was named after Schuyler Colfax, the vice president from 1869–73.